Grizzlies Ballpark is a minor league baseball facility in Sauget, Illinois, that serves as the home ballpark for the Gateway Grizzlies of the Frontier League. Grizzlies Ballpark features reserved box seating, lawn seating, party suites, two hot tubs, and a section of bleacher seating. With the bleacher section added in 2004, the stadium's capacity has increased to 6,000 fans. In 2004, the Grizzlies became the first team in Frontier League history to draw over 200,000 fans for a season, finishing with a league best 217,500. ProGrass synthetic turf was installed in January 2012.

Grizzlies Ballpark was built in time for the start of the 2002 season, under the original name of GMC Stadium. It was renamed GCS Ballpark for the 2006 season. When that naming rights deal ran out before the 2023 season it became Grizzlies Ballpark.

Grizzlies Ballpark hosted the 2008 NCAA Division II Baseball Championship. The stadium hosts the annual wood-bat college baseball game between the Billikens of Saint Louis University and the Salukis of Southern Illinois University. The ballpark also serves as the home field of Webster University's baseball team. It was home field for the now-defunct Lindenwood University – Belleville.

Grizzlies Ballpark sells a unique food item called "Baseball's Best Burger", a variant of the Luther Burger. It consists of a bacon cheeseburger with a Krispy Kreme Original Glazed doughnut used as a bun. The ballpark and the burger were showcased in a special baseball-themed episode in season 2 of the Travel Channel's Man v. Food along with their nachos.

• "Grizzlies Ballpark". Gateway Grizzlies. Retrieved April 23, 2023.
• "GCS Credit Union Ballpark". Webster University Athletics. Retrieved April 23, 2023.

Events and tenants
Preceded by Homer Stryker Field	Host of the FL All-Star Game GMC Stadium 2003	Succeeded by T.R. Hughes Ballpark