The Gateway Grizzlies will open the 2025 Frontier League season on Thursday, May 8, against the Evansville Otters. (Photo: Thomas Grove)
Cedric Williams
Senior Editor
SAUGET, IL –The Gateway Grizzlies made their final roster moves before the start of the 2025 Frontier League season on Monday.
The Grizzlies released rookie pitcher Jett Thielke and signed free agent outfielder Calyn Halvorson.
Gateway’s roster is now down to the league mandated 28 players and unless something surprising happens in the coming days, the Grizzlies’ roster for the new season is set.

Veteran 3B DJ Stewart will be back to lead the Gateway Grizzlies in 2025. (Photo: Thomas Grove)
Thielke signed with Gateway twice. First, as a free agent during the off-season. Then again, after the Grizzlies selected him in the Frontier League Draft two weeks ago.
He participated in Gateway’s spring training practices and even pitched in one of the Grizzlies’ preseason games. But he became the last player cut before the start of the season, when Gateway released him on Monday.
A major reason why Thielke was cut was the Grizzlies needed to make room for Halvorson, who signed with the team on Saturday. Thielke will be entering his second professional season, after playing last summer as a rookie for the Grand Junction Jackalopes of the Pioneer League.
In 2024, Halvorson hit .312, with 12 home runs and 50 RBIs in 67 games for Grand Junction. That was after completing his college career at Utah Valley State, where in two seasons, he hit 16 home runs and had 89 RBIs in 106 games played.

Calyn Halvorson hit 16 home runs and had 89 RBIs in two collegiate seasons at Utah Valley State. (Photo courtesy: Utah Valley State Athletics)
The Grizzlies will begin the 2025 Frontier League season on Thursday, May 8, when they’ll travel to Indiana to play a three-game series against the Evansville Otters at Bosse Field.
After the three games in Evansville, Gateway will travel down south to play a three-game set against the Mississippi Mud Monsters at Trustmark Park in Pearl, Miss.
The Grizzlies’ home opener will be Friday, May 16, at Grizzlies Ballpark against the Trois-Rivières Aigles.
2025 GATEWAY GRIZZLIES BASEBALL SCHEDULE
Date | Time | At | Opponent | Location |
---|---|---|---|---|
May 8, 2025 (Thursday) | 6:35 pm | Away | Evansville Otters | Evansville, IN / Bosse Field |
May 9, 2025 (Friday) | 6:35 pm | Away | Evansville Otters | Evansville, IN / Bosse Field |
May 10, 2025 (Saturday) | 6:35 pm | Away | Evansville Otters | Evansville, IN / Bosse Field |
May 13, 2025 (Tuesday) | 6:30 pm | Away | Mississippi Mud Monsters | Pearl, MS / Trustmark Park |
May 14, 2025 (Wednesday) | 6:30 pm | Away | Mississippi Mud Monsters | Pearl, MS / Trustmark Park |
May 15, 2025 (Thursday) | 6:30 pm | Away | Mississippi Mud Monsters | Pearl, MS / Trustmark Park |
May 16, 2025 (Friday) | 6:30 pm | Home | Trois-Rivières Aigles | Grizzlies Ballpark |
May 17, 2025 (Saturday) | 6:30 pm | Home | Trois-Rivières Aigles | Grizzlies Ballpark |
May 18, 2025 (Sunday) | 1:05 pm | Home | Trois-Rivières Aigles | Grizzlies Ballpark |
May 20, 2025 (Tuesday) | 6:40 pm | Away | Florence Y’alls | Florence, KY / Thomas More Stadium |
May 21, 2025 (Wednesday) | 6:40 pm | Away | Florence Y’alls | Florence, KY / Thomas More Stadium |
May 22, 2025 (Thursday) | 6:40 pm | Away | Florence Y’alls | Florence, KY / Thomas More Stadium |
May 23, 2025 (Friday) | 6:30 pm | Away | Schaumburg Boomers | Schaumburg, IL / Wintrust Field |
May 24, 2025 (Saturday) | 3 pm | Away | Schaumburg Boomers | Schaumburg, IL / Wintrust Field |
May 25, 2025 (Sunday) | 6:30 pm | Away | Schaumburg Boomers | Schaumburg, IL / Wintrust Field |
May 27, 2025 (Tuesday) | 6:30 pm | Home | Florence Y’alls | Grizzlies Ballpark |
May 28, 2025 (Wednesday) | 6:30 pm | Home | Florence Y’alls | Grizzlies Ballpark |
May 29, 2025 (Thursday) | 6:30 pm | Home | Florence Y’alls | Grizzlies Ballpark |
May 30, 2025 (Friday) | 6:30 pm | Home | Sussex County Miners | Grizzlies Ballpark |
May 31, 2025 (Saturday) | 6:30 pm | Home | Sussex County Miners | Grizzlies Ballpark |
June 1, 2025 (Sunday) | 1:05 pm | Home | Sussex County Miners | Grizzlies Ballpark |
June 3, 2025 (Tuesday) | 6:35 pm | Away | Windy City ThunderBolts | Crestwood, IL / Ozinga Field |
June 4, 2025 (Wednesday) | 6:35 pm | Away | Windy City ThunderBolts | Crestwood, IL / Ozinga Field |
June 5, 2025 (Thursday) | 6:35 pm | Away | Windy City ThunderBolts | Crestwood, IL / Ozinga Field |
June 6, 2025 (Friday) | 6:35 pm | Away | Joliet Slammers | Joliet, IL / Duly Health Care Field |
June 7, 2025 (Saturday) | 6:05 pm | Away | Joliet Slammers | Joliet, IL / Duly Health Care Field |
June 8, 2025 (Sunday) | 1:05 pm | Away | Joliet Slammers | Joliet, IL / Duly Health Care Field |
June 10, 2025 (Tuesday) | 6:30 pm | Away | Tri-City Valley Cats | Albany, NY / Bruno Stadium |
June 11, 2025 (Wednesday) | 10 am | Away | Tri-City Valley Cats | Albany, NY / Bruno Stadium |
June 12, 2025 (Thursday) | 6:30 pm | Away | Tri-City Valley Cats | Albany, NY / Bruno Stadium |
June 13, 2025 (Friday) | 6 pm | Away | New York Boulders | Pomano, NY / Clover Stadium |
June 14, 2025 (Saturday) | 5:30 pm | Away | New York Boulders | Pomano, NY / Clover Stadium |
June 15, 2025 (Sunday) | 12 pm | Away | New York Boulders | Pomano, NY / Clover Stadium |
June 17, 2025 (Tuesday) | 6:30 pm | Home | Schaumburg Boomers | Grizzlies Ballpark |
June 18, 2025 (Wednesday) | 6:30 pm | Home | Schaumburg Boomers | Grizzlies Ballpark |
June 19, 2025 (Thursday) | 6:30 pm | Home | Schaumburg Boomers | Grizzlies Ballpark |
June 20, 2025 (Friday) | 6:30 pm | Home | Mississippi Mud Monsters | Grizzlies Ballpark |
June 21, 2025 (Saturday) | 6:30 pm | Home | Mississippi Mud Monsters | Grizzlies Ballpark |
June 22, 2025 (Sunday) | 5:30 pm | Home | Mississippi Mud Monsters | Grizzlies Ballpark |
June 24, 2025 (Tuesday) | 6:30 pm | Home | Evansville Otters | Grizzlies Ballpark |
June 25, 2025 (Wednesday) | 6:30 pm | Home | Evansville Otters | Grizzlies Ballpark |
June 26, 2025 (Thursday) | 10:45 am | Home | Evansville Otters | Grizzlies Ballpark |
June 27, 2025 (Friday) | 6:30 pm | Away | Lake Erie Crushers | Avon, OH / Crushers Stadium |
June 28, 2025 (Saturday) | 6:30 pm | Away | Lake Erie Crushers | Avon, OH / Crushers Stadium |
June 29, 2025 (Sunday) | 6:30 pm | Away | Lake Erie Crushers | Avon, OH / Crushers Stadium |
July 1, 2025 (Tuesday) | 6:30 pm | Home | Washington Wild Things | Grizzlies Ballpark |
July 2, 2025 (Wednesday) | 6:30 pm | Home | Washington Wild Things | Grizzlies Ballpark |
July 3, 2025 (Thursday) | 7:05 pm | Home | Washington Wild Things | Grizzlies Ballpark |
July 4, 2025 (Friday) | 7:05 pm | Home | Lake Erie Crushers | Grizzlies Ballpark |
July 5, 2025 (Saturday) | 7:05 pm | Home | Lake Erie Crushers | Grizzlies Ballpark |
July 6, 2025 (Sunday) | 5:30 pm | Home | Lake Erie Crushers | Grizzlies Ballpark |
July 8, 2025 (Tuesday) | 6:30 pm | Home | Joliet Slammers | Grizzlies Ballpark |
July 9, 2025 (Wednesday) | 6:30 pm | Home | Joliet Slammers | Grizzlies Ballpark |
July 10, 2025 (Thursday) | 10:45 am | Home | Joliet Slammers | Grizzlies Ballpark |
July 11, 2025 (Friday) | 6:35 pm | Away | Evansville Otters | Evansville, IN / Bosse Field |
July 12, 2025 (Saturday) | 6:35 pm | Away | Evansville Otters | Evansville, IN / Bosse Field |
July 13, 2025 (Sunday) | 5:05 pm | Away | Evansville Otters | Evansville, IN / Bosse Field |
July 16, 2025 (Wednesday) | 6 pm | Neutral | Frontier League All-Star Game (hosted by Tri-City Valley Cats) | Albany, NY / Bruno Stadium |
July 18, 2025 (Friday) | 6:30 pm | Home | Schaumburg Boomers | Grizzlies Ballpark |
July 19, 2025 (Saturday) | 6:30 pm | Home | Schaumburg Boomers | Grizzlies Ballpark |
July 20, 2025 (Sunday) | 5:30 pm | Home | Schaumburg Boomers | Grizzlies Ballpark |
July 22, 2025 (Tuesday) | 6:35 pm | Away | Joliet Slammers | Joliet, IL / Duly Health Care Field |
July 23, 2025 (Wednesday) | 10:05 am | Away | Joliet Slammers | Joliet, IL / Duly Health Care Field |
July 24, 2025 (Thursday) | 6:35 pm | Away | Joliet Slammers | Joliet, IL / Duly Health Care Field |
July 25, 2025 (Friday) | 6:35 pm | Away | Windy City ThunderBolts | Crestwood, IL / Ozinga Field |
July 26, 2025 (Saturday) | 6:05 pm | Away | Windy City ThunderBolts | Crestwood, IL / Ozinga Field |
July 27, 2025 (Sunday) | 1:05 pm | Away | Windy City ThunderBolts | Crestwood, IL / Ozinga Field |
July 29, 2025 (Tuesday) | 6:30 pm | Home | Joliet Slammers | Grizzlies Ballpark |
July 30, 2025 (Wednesday) | 6:30 pm | Home | Joliet Slammers | Grizzlies Ballpark |
July 31, 2025 (Thursday) | 6:30 pm | Home | Joliet Slammers | Grizzlies Ballpark |
August 1, 2025 (Friday) | 6:30 pm | Home | Windy City ThunderBolts | Grizzlies Ballpark |
August 2, 2025 (Saturday) | 6:30 pm | Home | Windy City ThunderBolts | Grizzlies Ballpark |
August 3, 2025 (Sunday) | 5:30 pm | Home | Windy City ThunderBolts | Grizzlies Ballpark |
August 5, 2025 (Tuesday) | 6:30 pm | Home | Mississippi Mud Monsters | Grizzlies Ballpark |
August 6, 2025 (Wednesday) | 6:30 pm | Home | Mississippi Mud Monsters | Grizzlies Ballpark |
August 7, 2025 (Thursday) | 10:45 am | Home | Mississippi Mud Monsters | Grizzlies Ballpark |
August 8, 2025 (Friday) | 6:05 pm | Away | Washington Wild Things | Washington, PA / EQT Park |
August 9, 2025 (Saturday) | 6:05 pm | Away | Washington Wild Things | Washington, PA / EQT Park |
August 10, 2025 (Sunday) | 4:35 pm | Away | Washington Wild Things | Washington, PA / EQT Park |
August 12, 2025 (Tuesday) | 6:30 pm | Home | Lake Erie Crushers | Grizzlies Ballpark |
August 13, 2025 (Wednesday) | 6:30 pm | Home | Lake Erie Crushers | Grizzlies Ballpark |
August 14, 2025 (Thursday) | 6:30 pm | Home | Lake Erie Crushers | Grizzlies Ballpark |
August 15, 2025 (Friday) | 6:30 pm | Home | Windy City ThunderBolts | Grizzlies Ballpark |
August 16, 2025 (Saturday) | 7:15 pm | Home | Windy City ThunderBolts | Grizzlies Ballpark |
August 17, 2025 (Sunday) | 5:30 pm | Home | Windy City ThunderBolts | Grizzlies Ballpark |
August 19, 2025 (Tuesday) | 6:30 pm | Away | Schaumburg Boomers | Schaumburg, IL / Wintrust Field |
August 20, 2025 (Wednesday) | 6:30 pm | Away | Schaumburg Boomers | Schaumburg, IL / Wintrust Field |
August 21, 2025 (Thursday) | 6:30 pm | Away | Schaumburg Boomers | Schaumburg, IL / Wintrust Field |
August 22, 2025 (Friday) | 7:05 pm | Away | Florence Y’alls | Florence, KY / Thomas More Stadium |
August 23, 2025 (Saturday) | 6:35 pm | Away | Florence Y’alls | Florence, KY / Thomas More Stadium |
August 24, 2025 (Sunday) | 1:05 pm | Away | Florence Y’alls | Florence, KY / Thomas More Stadium |
August 26, 2025 (Tuesday) | 6:30 pm | Away | Mississippi Mud Monsters | Pearl, MS / Trustmark Park |
August 27, 2025 (Wednesday) | 11 am | Away | Mississippi Mud Monsters | Pearl, MS / Trustmark Park |
August 28, 2025 (Thursday) | 6:30 pm | Away | Mississippi Mud Monsters | Pearl, MS / Trustmark Park |
August 29, 2025 (Friday) | 6:30 pm | Home | Evansville Otters | Grizzlies Ballpark |
August 30, 2025 (Saturday) | 6:30 pm | Home | Evansville Otters | Grizzlies Ballpark |
August 31, 2025 (Sunday) | 6:05 pm | Home | Evansville Otters | Grizzlies Ballpark |
September 3-6, 2025 | TBD | TBD | Frontier League Wild Card Round | TBD |
September 9-14, 2025 | TBD | TBD | Frontier League Divisional Championship Series | TBD |
September 16-21, 2025 | TBD | TBD | Frontier League Championship Series | TBD |