The Frontier League (FL; French: Ligue Frontière, LF) is a professional baseball league in North America composed of 15 teams in the United States and 3 in Canada. The league is an official MLB Partner League and is the oldest active independent professional baseball league in North America. The FL is headquartered at the Crushers' ballpark in Avon, Ohio.

In April 2026, the league announced that it would rebrand as the National Association of Professional Baseball (NAPB) beginning with the 2027 season. The league stated that its history, statistics and records would continue under the new identity.

At its inception, the FL had eight teams, all in the United States. The league expanded to Canada in 1999, when the London Werewolves joined. From 2008 to 2019, the league operated with several different franchise structures, peaking with 14 teams. The league added five teams as a result of the Can-Am and Frontier Leagues merger in 2020, increased to 16 teams by 2021, and reached 18 teams with 2025 expansion clubs in Pearl, Mississippi, and Kinston, North Carolina. The Mississippi Mud Monsters were established at Trustmark Park following the departure of the Mississippi Braves, while the Down East Bird Dawgs were established at Grainger Stadium following the departure of the Down East Wood Ducks.

The league's regular season is typically held from May to September, with each team playing 96 games. Following the conclusion of the regular season, eight teams advance to the Frontier League playoffs, a three-round tournament that runs into late September to determine the league champion. The reigning league champions are the Québec Capitales, who defeated the Schaumburg Boomers in five games in the 2025 Frontier League Championship Series to win their fourth consecutive league title.

History

Early years

The Frontier League was founded in 1993. It initially struggled to retain franchises, with four of its eight founding teams folding within three seasons, though it steadily grew to twelve teams within a decade. The first league champions were the Zanesville Greys. Eight teams have won more than one championship: Springfield in 1996 and 1998; Johnstown in 1995 as the Steal and in 2000 as the Johnnies; Richmond Roosters in 2001 and 2002; Windy City in 2007 and 2008; the Joliet Slammers in 2011 and 2018; the Evansville Otters in 2006 and 2016; the Schaumburg Boomers in 2013, 2014, 2017 and 2021; and the Québec Capitales in 2022, 2023, 2024 and 2025. With four titles each, the Boomers and Capitales are tied for the most league championships.

On June 20, 2000, Brian Tollberg debuted with the San Diego Padres, becoming the first FL player to make it to the major leagues. A week later, Morgan Burkhart made his debut with the Boston Red Sox.

Although the league does not have any teams located in the same city as Major League teams, several Frontier League teams play within Major League Baseball markets. The Chicago area has three teams, the Joliet Slammers, Schaumburg Boomers and Windy City ThunderBolts, while the New York area has the New Jersey Jackals, Sussex County Miners and New York Boulders. Other markets include St. Louis with the Gateway Grizzlies, Cleveland with the Lake Erie Crushers, Cincinnati with the Florence Y'alls and Pittsburgh with the Washington Wild Things.

League merger

On October 16, 2019, it was announced that the Frontier League would merge with the Can-Am League, absorbing five of its teams to form the largest independent professional baseball league. This added the New Jersey Jackals, New York Boulders, Québec Capitales, Sussex County Miners and Trois-Rivières Aigles to the league. The Ottawa Champions, the last remaining Can-Am League team, were not invited to participate. The divisions were renamed, with the easternmost teams playing in the Can-Am Division and the westernmost teams playing in the Midwest Division.

On September 24, 2020, Major League Baseball announced that it named the FL as an MLB Partner League. This enabled collaboration with MLB to jointly discuss marketing and promotional initiatives to grow, expand and enhance the game and quality of baseball.

Border issues

For the 2021 season, the league announced that it would add two new teams. The first announcement came around the same time as the announcement of the partnership with Major League Baseball, as Ottawa was granted an expansion franchise in the league. The team, as chosen by fans in a contest, was named the Titans and started playing at Ottawa Stadium. Then, on January 8, 2021, after the reorganization of Minor League Baseball, the league added the Tri-City ValleyCats, which were one of several teams left without affiliation when the New York-Penn League was folded. The Titans, ValleyCats and Washington Wild Things joined the five former Can-Am League teams in the Can-Am Division, while Lake Erie was transferred to the Midwest Division.

On April 22, 2021, the league announced that the Québec Capitales, Trois-Rivières Aigles and Ottawa Titans would not compete in the 2021 season due to the prolonged closure of the Canada–United States border as a result of the COVID-19 pandemic. The Titans, Aigles and Capitales later joined forces to form a new team that competed as a member of the Atlantic Division in the Can-Am Conference. Known as Équipe Québec, they began the season as a traveling team. Starting on July 30, 2021, they shared home games between Quebec City and Trois-Rivières following a loosening in border restrictions. The team played 10 games in Québec City and 11 in Trois-Rivières. It did not play in Ottawa due to COVID-19 restrictions in Ontario.

Expansion era

On October 6, 2021, the owners of the Southern Illinois Miners, Jayne and John Simmons, announced they would be retiring from professional baseball to spend more time with family. The Miners ceased operations and dropped out of the FL. As a result, the league formed the Empire State Greys, a traveling team with a roster of players from the Empire Professional Baseball League.

In September 2023, the league announced a new team, the New England Knockouts, planned to play at Campanelli Stadium in Brockton, Massachusetts, beginning with the 2024 season. This brought the total number of permanent members of the league to sixteen teams. After playing one season as the Knockouts, the team was renamed the Brockton Rox in January 2025.

In September 2024, the league announced expansion clubs in Mississippi and North Carolina. following the departure of the Atlanta Braves Double-A affiliate, the Mississippi Braves. The additions brought the league to 18 teams.

Rebrand to National Association of Professional Baseball

On April 22, 2026, the Frontier League announced that it would rebrand as the National Association of Professional Baseball beginning with the 2027 season.

The league's regular season standings are based on winning percentage. At the end of the regular season, the team that finishes with the highest winning percentage in each division is crowned division champion.

The Frontier League playoffs are an elimination tournament. Four teams from each conference qualify: the top team in each division plus the two conference teams with the next highest winning percentage. The two Wild Card Series winners proceed to the Frontier League Division Series as the league's conference finals, and the two conference champions proceed to the Frontier League Championship Series. In all rounds, the higher-ranked team is awarded home-field advantage, with up to three games played at that team's home venue. In the championship series, the team with the most regular season wins receives home-field advantage. The remaining six players on the 24-man roster can be classified as Experienced-1 or Experienced-2. Rosters are limited to 24 players for the Opening Day series, although up to 10 additional players can be added to a team's roster during the regular season before the transactions limit.

Teams

For the 2021 season, the Frontier League consisted of 14 teams, 13 based in the United States and one in Canada. The FL divided the 14 teams into two conferences: the Can-Am Conference and the Midwest Conference. Each conference was split into two divisions. The league temporarily realigned from the 2022 to the 2024 seasons but returned to a two-conference, four-division alignment for the 2025 season. With the addition of the Empire State Greys in 2022–2023 and the Brockton Rox in 2024, the league operated at 16 teams with two divisions, East and West.

The league expanded to 15 teams with the addition of the Ottawa Titans in 2020, then to 16 with the addition of the Tri-City ValleyCats in 2021. In September 2024, a new expansion team in Mississippi was created following the departure of the Mississippi Braves. A second new team in Kinston, North Carolina, joined the FL and started playing in 2025 as the Down East Bird Dawgs. The expansion brought the league to 18 teams and marked its first expansion into the Deep South. The league reverted to a two-conference, four-division setup.

List of teams

{| class="wikitable sortable plainrowheaders" style="text-align:left"

|+Overview of FL teams

|-

! scope="col" align="center"|Conference

! scope="col" align="center"|Division

! scope="col" align="center"|Team

! scope="col" align="center"|City

! scope="col" align="center"|Stadium

! scope="col" align="center"|Capacity

! scope="col" align="center"|Founded

! scope="col" align="center"|Joined

! scope="col" align="center"|General manager

! scope="col" align="center"|Manager

|-

!rowspan="9" |Atlantic

! rowspan="4"|East

!scope="row"| Down East Bird Dawgs

| Kinston, North Carolina

| Grainger Stadium

| align=center | 3,400

| colspan="2" style="text-align:center;" | 2025

| Shari Massengill

| Brett Wellman

|-

!scope="row"| New Jersey Jackals

| Paterson, New Jersey

| Hinchliffe Stadium

| align=center | 7,800

| style="text-align:center;" | 1998

|2020

| John Hunt

| Albert Gonzalez

|-

!scope="row"| New York Boulders

| Pomona, New York

| Clover Stadium

| align=center | 8,362

| style="text-align:center;" | 2011

|2020

| Shawn Reilly

| T.J. Stanton

|-

!scope="row"| Sussex County Miners

| Augusta, New Jersey

| Skylands Stadium

| align=center | 4,200

| style="text-align:center;" | 2015

|2020

| Vincent Sangemino

| Chris Widger

|-

! rowspan="5"|North

!scope="row"| Brockton Rox

| Brockton, Massachusetts

| Campanelli Stadium

| align=center | 4,750

| colspan="2" align="center" | 2024

| Connor Carey

| Jerod Edmondson

|-

!scope="row"| Ottawa Titans

| Ottawa, Ontario

| Ottawa Stadium

| align=center | 10,332

| colspan="2" style="text-align:center;" | 2021

| Martin Boyce

| Bobby Brown

|-

!scope="row"| Québec Capitales

| Quebec City, Quebec

| Stade Canac

| align=center | 4,297

| style="text-align:center;" | 1999

|2020

| Mike Petillion

| Patrick Scalabrini

|-

!scope="row"| Tri-City ValleyCats

| Troy, New York

| Joseph L. Bruno Stadium

| align=center | 6,500

| style="text-align:center;" | 2002

|2021

| Matt Callahan

| Greg Tagert

|-

!scope="row"| Trois-Rivières Aigles

| Trois-Rivières, Quebec

| Stade Quillorama

| align=center | 4,000

| style="text-align:center;" | 2013

|2020

| Simon Laliberté

| Jonathan Albaladejo

|-

!rowspan="9" |Midwest

! rowspan="4"|Central

!scope="row"| Evansville Otters

| Evansville, Indiana

| Bosse Field

| align=center | 5,181

| colspan="2" style="text-align:center;" | 1995

|Travis Painter

| Andy McCauley

|-

!scope="row"| Florence Y'alls

| Florence, Kentucky

| Thomas More Stadium

| align=center | 4,500

| colspan="2" align="center" | 2003

| Max Johnson

| Chad Rhoades

|-

!scope="row"| Lake Erie Crushers

| Avon, Ohio

| ForeFront Field

| align=center | 5,000

| colspan="2" style="text-align:center;" | 2009

|Brian Wentzel

| Jared Lemieux

|-

!scope="row"| Washington Wild Things

| Washington, Pennsylvania

| EQT Park

| align=center | 3,200

| colspan="2" style="text-align:center;" | 2002

| Tony Bucilli

| Tom Vaeth

|-

! rowspan="5"|West

!scope="row"| Gateway Grizzlies

| Sauget, Illinois

| Arsenal BG Ballpark

| align=center | 6,000

| colspan="2" style="text-align:center;" | 2001

| Kurt Ringkamp

| Steve Brook

|-

!scope="row"| Joliet Slammers

| Joliet, Illinois

| Duly Health and Care Field

| align=center | 6,016

| colspan="2" style="text-align:center;" | 2011

| Bruce Maddox III

| Mike Pinto

|-

!scope="row"| Mississippi Mud Monsters

| Pearl, Mississippi

| Trustmark Park

| align=center | 6,500

| colspan="2" align="center" | 2025

| Andrew Seymour

| Jay Pecci

|-

!scope="row"| Schaumburg Boomers

| Schaumburg, Illinois

| Wintrust Field

| align=center | 5,665

| colspan="2" style="text-align:center;" | 2012

| Michael Larson

| Jamie Bennett

|-

!scope="row"| Windy City ThunderBolts

| Crestwood, Illinois

| Ozinga Field

| align=center | 3,500

| style="text-align:center;" | 1995

|1999

| Mike VerSchave

| Toby Hall

|}

Former teams

  • Canton Coyotes (2002, became the Mid-Missouri Mavericks)
  • Canton Crocodiles (1997–2002, became the Washington Wild Things)
  • Chillicothe Paints (1993–2008, joined the Prospect League)
  • Dubois County Dragons (2000–2002, became the Kenosha Mammoths)
  • Empire State Greys (2022–2023, temporary travel team)
  • Équipe Québec (2021, temporary travel team consisting of Canadian players from Ottawa, Québec and Trois-Rivières operated due to COVID-19 pandemic travel restrictions)
  • Erie Sailors (1994, became the Johnstown Steal)
  • Florence Freedom (2003–2019, became the Florence Y'alls)
  • Frontier Greys (2013–2015, temporary travel team)
  • Johnstown Johnnies (1998–2002, became the Florence Freedom)
  • Johnstown Steal (1995–1998, became the Johnstown Johnnies)
  • Kalamazoo Kings (2001–2010, folded)
  • Kalamazoo Kodiaks (1996–1998, became the London Werewolves)
  • Kenosha Mammoths (2003, became the Springfield-Ozark Ducks)
  • Kentucky Rifles (1993–1994, folded)
  • Lancaster Scouts (1993–1994, became the Evansville Otters)
  • London Rippers (2012, folded)
  • London Werewolves (1999–2001, became the Canton Coyotes)
  • Mid-Missouri Mavericks (2003–2005, folded)
  • Midwest Sliders (2008–2009, became the Oakland County Cruisers)
  • Normal CornBelters (2010–2018, joined the Prospect League)
  • Newark Buffaloes (1994–1995, became the Kalamazoo Kodiaks)
  • New England Knockouts (2024, became the Brockton Rox)
  • Oakland County Cruisers (2010–2011, became the London Rippers)
  • Ohio Valley Redcoats (1993–1998, returned 2005, folded)
  • Portsmouth Explorers (1993–1995, became the Springfield Capitals)
  • Richmond Roosters (1995–2005, became the Traverse City Beach Bums)
  • River City Rascals (1999–2019, folded)
  • Rockford Aviators (2013–2015, folded)
  • Rockford RiverHawks (2002–2009, moved to Northern League; returned 2011–2012, became Rockford Aviators)
  • Slippery Rock Sliders (2007, became the Midwest Sliders)
  • Southern Illinois Miners (2007–2021, folded)
  • Springfield Capitals (1996–2001, became the Rockford RiverHawks)
  • Springfield-Ozark Ducks (2004, became the Ohio Valley Redcoats)
  • Traverse City Beach Bums (2006–2018, folded)
  • Tri-State Tomahawks (1993, folded)
  • West Virginia Coal Sox (1993, folded)
  • Zanesville Greys (1993–1996, became the River City Rascals)

Timeline

<timeline>

DateFormat = mm/dd/yyyy

ImageSize = width:1100 height:auto barincrement:20

Period = from:1993 till:2027

TimeAxis = orientation:horizontal

PlotArea = right:40 left:0 bottom:50 top:5

Colors = id:barcolor value:rg(0.99,0.7,0.7)

id:line value:black

id:bg value:white

PlotData=

width:15 textcolor:black shift:(5,-5) anchor:from fontsize:s

bar:1 color:orange from:05/15/1993 till:09/20/2008 text:Chillicothe Paints (1993–2008)

bar:2 color:orange from:05/15/1993 till:09/20/1994 text:Kentucky Rifles (1993–94)

bar:3 color:orange from:05/15/1993 till:end text:Lancaster Scouts (1993–94), Evansville Otters (1995–)

bar:4 color:orange from:05/15/1993 till:09/20/2005 text:Ohio Valley Redcoats (1993–98, 2005), Dubois County Dragons (1999–2002), Kenosha Mammoths (2003), Springfield-Ozark Ducks (2004)

bar:5 color:orange from:05/15/1993 till:09/20/2009 text:Portsmouth Explorers (1993–95), Springfield Capitals (1996–2001), Rockford RiverHawks (2002–09, 2011–12), Rockford Aviators (2013–15)

bar:5 color:orange from:05/15/2011 till:09/20/2015

bar:6 color:orange from:05/15/1993 till:07/10/1993 text:Tri-State Tomahawks (1993)

bar:7 color:orange from:05/15/1993 till:06/30/1993 text:West Virginia Coal Sox (1993)

bar:8 color:orange from:05/15/1993 till:09/20/1996 text:Zanesville Greys (1993–96)

bar:8 color:orange from:05/15/1999 till:09/15/2019 text:River City Rascals (1999–2019)

bar:9 color:orange from:05/15/1994 till:end text:Erie Sailors (1994), Johnstown Steal (1995–98), Johnstown Johnnies (1999–2002), Florence Freedom (2003–19), Florence Y'alls (2020–)

bar:10 color:orange from:05/15/1994 till:09/20/2005 text:Newark Buffaloes/Bison (1994–95), Kalamazoo Kodiaks (1996–98), London Werewolves (1999–2001), Canton Coyotes (2002), Mid-Missouri Mavericks (2003–05)

bar:11 color:orange from:05/15/1995 till:09/26/2018 text:Richmond Roosters (1995–2005), Traverse City Beach Bums (2006–18)

bar:12 color:orange from:05/15/1997 till:end text:Canton Crocodiles (1997–2001), Washington Wild Things (2002–)

bar:13 color:orange from:05/15/1999 till:end text:Cook County Cheetahs (1999–2003), Windy City ThunderBolts (2004–)

bar:14 color:orange from:05/15/2001 till:end text:Gateway Grizzlies (2001–)

bar:15 color:orange from:05/15/2001 till:09/20/2008 text:Kalamazoo Kings (2001–10)

bar:16 color:orange from:05/15/2007 till:07/25/2012 text:Slippery Rock Sliders (2007), Midwest Sliders (2008), Midwest Sliders of Ypsilanti (2009), Oakland County Cruisers (2010), London Rippers (2012)

bar:17 color:orange from:05/15/2007 till:09/12/2021 text:Southern Illinois Miners (2007–21)

bar:18 color:orange from:05/15/2009 till:end text:Lake Erie Crushers (2009–)

bar:19 color:orange from:05/15/2010 till:09/26/2018 text:Normal CornBelters (2010–18)

bar:20 color:orange from:05/15/2011 till:end text:Joliet Slammers (2011–)

bar:21 color:orange from:05/15/2012 till:end text:Schaumburg Boomers (2012–)

bar:22 color:orange from:07/25/2012 till:10/31/2012 text:Road Warriors (2012)

bar:23 color:orange from:05/25/2013 till:09/30/2015 text:Frontier Greys (2013–15)

bar:24 color:orange from:05/15/2020 till:end text:New Jersey Jackals (2020–)

bar:25 color:orange from:05/15/2020 till:end text:New York Boulders (2020–)

bar:26 color:orange from:05/15/2020 till:end text:Québec Capitales (2020–)

bar:27 color:orange from:05/15/2020 till:end text:Sussex County Miners (2020–)

bar:28 color:orange from:05/15/2020 till:end text:Trois-Rivières Aigles (2020–)

bar:29 color:orange from:05/15/2021 till:end text:Ottawa Titans (2021–)

bar:30 color:orange from:05/27/2021 till:end text:Tri-City ValleyCats (2021–)

bar:31 color:orange from:05/27/2021 till:09/19/2021 text:Équipe Québec (2021)

bar:32 color:orange from:05/27/2022 till:09/17/2023 text:Empire State Greys (2022–2023)

bar:33 color:orange from:05/10/2024 till:end text:Brockton Rox (2024–)

bar:34 color:orange from:05/01/2025 till:end text:Down East Bird Dawgs (2025–)

bar:35 color:orange from:05/01/2025 till:end text:Mississippi Mud Monsters (2025–)

ScaleMajor = gridcolor:line unit:year increment:2 start:1993

TextData =

fontsize:L

textcolor:black

pos:(175,30)

text:"Frontier League Franchise History"

</timeline>

Champions

  • 1993 Zanesville Greys
  • 1994 Erie Sailors
  • 1995 Johnstown Steal
  • 1996 Springfield Capitals
  • 1997 Canton Crocodiles
  • 1998 Springfield Capitals
  • 1999 London Werewolves
  • 2000 Johnstown Johnnies
  • 2001 Richmond Roosters
  • 2002 Richmond Roosters
  • 2003 Gateway Grizzlies
  • 2004 Rockford RiverHawks
  • 2005 Kalamazoo Kings
  • 2006 Evansville Otters
  • 2007 Windy City ThunderBolts
  • 2008 Windy City ThunderBolts
  • 2009 Lake Erie Crushers
  • 2010 River City Rascals
  • 2011 Joliet Slammers
  • 2012 Southern Illinois Miners
  • 2013 Schaumburg Boomers
  • 2014 Schaumburg Boomers
  • 2015 Traverse City Beach Bums
  • 2016 Evansville Otters
  • 2017 Schaumburg Boomers
  • 2018 Joliet Slammers
  • 2019 River City Rascals
  • 2020 Season cancelled due to COVID-19 pandemic
  • 2021 Schaumburg Boomers
  • 2022 Québec Capitales
  • 2023 Québec Capitales
  • 2024 Québec Capitales
  • 2025 Québec Capitales

Records

Individual career records

Batting

{| class="wikitable"

|+

!Statistic

!Record

!Player

|-

|Games Played

|745

| rowspan="4" |Santiago Chirino

|-

|At Bats

|2,928

|-

|Runs

|452

|-

|Hits

|929

|-

|Home Runs

|127

| rowspan="2" |Charlie Lisk

|-

|Runs Batted In

|442

|}

Pitching

{| class="wikitable"

|+

!Statistic

!Record

!Player

|-

|Games

|300

|Jake Joyce

|-

|Games started

|121

| rowspan="4" |Zac Westcott

|-

|Innings Pitched

|781.2

|-

|Wins

|53

|-

|Strikeouts

|621

|-

|Complete Games

|18

|Aaron Ledbetter

|-

|Saves

|74

|Zach Strecker

|}

Broadcasting

On February 24, 2022, the FL announced that all games for the 2022 season would be available through the streaming platform FloSports. In 2025, the league moved its streaming broadcasts to the Frontier League Network, powered by HomeTeam Network, as part of a multi-year streaming and broadcast partnership.

See also

  • Baseball awards#U.S. independent professional leagues

Notes

  • Official website
  • Frontier League History
  • Frontier League Encyclopedia and History at Baseball Reference