About Us


Who are the Windy City ThunderBolts?
The Windy City ThunderBolts are a professional minor league baseball based out of Crestwood, Illinois and a member of the Frontier League, a MLB Partner League, since 1999.  We are proud to be the official minor league team of the Chicago Southland.  We were formerly known as the Cook County Cheetahs, but in 2004 we received a new ownership group, name, mascot, and a new look at minor league baseball.  The Cheetah/ThunderBolts franchise has existed since 1995.  The 2024 season will be the organization's 29th overall and in those years the club has gone through three leagues, three stadiums, two names, five playoff appearances, and three championships.  For more information on the history of the club please go to the Team History Page on this website.

How long has the Frontier League Existed?
In the winter of 1992-1993, several men got together and decided to start an independent professional baseball league to serve the West Virginia, eastern Kentucky and southeast Ohio areas.  The goal of the league was to bring professional baseball to places that affiliated baseball wouldn't go.  Ironically the league is now part of Major League Baseball as an official Partner League.  What started as eight teams playing in municipal parks has become an international circuit that features sixteen teams in eight states and two Canadian provinces.  The Frontier League is North America's oldest continually operating Partner League of Major League Baseball entering it's 31st season in 2024.
What is a MLB Partner League?
While the Frontier League is a part of Major League Baseball minor league structure, it is not specifically affiliated with any MLB team.  Any MLB club can sign Frontier League players and put them into their own system.  All 30 Major League Baseball teams have signed Frontier League players. The Mariners, Marlins, Padres, Pirates, Rangers, Rays and White Sox currently have former ThunderBolts' players or coaches in their organizations. There are 51 players who have reached the Major Leagues after playing in the Frontier League, including the Cook County Cheetah’s Chris Oxspring (Padres 2005), ThunderBolts' pitchers Dylan Axelrod (White Sox 2011-13 and Reds 14-15), Andrew Werner (Padres 2012), Tommy Nance (Cubs 2021 and Marlins 2022) and Adam Oller (Athletics 2022-23).  The Frontier League has over six hundred former players who have been signed into MLB affiliated systems which is the most among MLB Partner Leagues.  The ThunderBolts organization is the team to play for if you want to get noticed as the club has had over 60 player contracts sold to Major League organizations, easily the most in the Frontier League.

Where do the Windy City ThunderBolts play?
The ThunderBolts play at Ozinga Field which is located in Crestwood, Illinois.  Ozinga Field is easily accessible from anywhere in Chicagoland, two blocks east of Cicero Avenue off the Midlothian Turnpike, just 1.5 miles south of I-294.  The facility is unique for its intimacy, while still holding championship sized crowds.  Catered picnic areas and skybox suites are available for rental and are great for group outings. There are two concession stands with a wide menu as well as a grill and beer garden. Ozinga Field also features one of the few upper decks in minor league baseball.

Who are the players?
The Frontier League is the premier developmental professional league in the country.  Only two players on the roster may have turned 30 or older by September 30th of the year in which they wish to play.  Over 65% of the players in the Frontier League enter with previous professional experience, with the remaining having recently completed college baseball.  They are paid to play and come from all over the country and even outside the United States.  At this level, the players always play hard and have a strong passion for the game.
How long is the season?
The ThunderBolts regular season consists of 48 home games and 48 road games (a total of 96), running from May 9th to August 31st.  The Playoffs start on September 3rd in which the top three teams in each division participate.