The Chicago White Sox erased a three-run deficit and handed the St. Louis Cardinals a gut-punch 6-5 loss at Busch Stadium on Saturday, September 12, 2026. Cooper Hjerpe's one-inning meltdown — four earned runs on two hits and four walks — unraveled what had looked like a comfortable Cardinals lead, and Riley O'Brien absorbed the loss after allowing two runs in the ninth. Nathan Church went 3-for-4, Masyn Winn drove in two, and Leo Bernal homered, but the St. Louis offense couldn't hold up its end once the bullpen gave the game away.

Cardinals Offense Puts Up a Fight but Falls Short

St. Louis generated plenty of contact on Saturday night. Nathan Church led the way with a 3-for-4 performance and an RBI, giving the Cardinals early momentum against a White Sox pitching staff that cycled through six arms. Masyn Winn was productive in his four at-bats, going 2-for-4 with two RBI. Leo Bernal added a solo home run — his lone hit in five at-bats — to keep the Cardinals in the fight late.

Chicago's starter Sean Newcomb lasted only 1.1 innings, and Luis Castillo followed with 2.2 frames that cost the White Sox three earned runs on four hits and three walks. That early pitching instability allowed St. Louis to build its lead. But the Cardinals couldn't add insurance runs when it mattered most, and that margin evaporated quickly once Hjerpe took the mound.

Cooper Hjerpe's Implosion Flips the Game

The turning point was not subtle. Hjerpe entered and turned a manageable situation into a disaster, surrendering four earned runs on two hits and four walks across a single inning of work. Four walks in one inning is the kind of damage that no bullpen can survive, and St. Louis couldn't. The Cardinals went from ahead to chasing in the span of one arm.

Kyle Leahy had actually given St. Louis a strong start to the game — three scoreless innings, four strikeouts, two hits allowed, zero walks — but the back end of the bullpen couldn't hold the lead Leahy and the offense built. Luis Gastelum, Justin Bruihl, Ryne Stanek, and George Soriano all kept the Cardinals close after Hjerpe's meltdown, but Riley O'Brien was handed the ball in the ninth and gave up two earned runs, allowing the White Sox to complete the comeback.

Randal Grichuk Does the Damage for Chicago

Former Cardinals outfielder Randal Grichuk provided the biggest blow for Chicago, going 1-for-4 with a home run and two RBI. Grichuk's contributions were central to the White Sox comeback, putting runs on the board at critical moments. Sam Antonacci went 2-for-4 to set the table, and Jordan Hicks earned the win despite recording just one out — a quirk of bullpen rules that underscored how chaotic the final innings were. Bryan Hudson closed it out with a clean ninth for the save.

By the Numbers: Key Performances

Cardinals Standouts

  • Nathan Church: 3-for-4, 1 RBI
  • Masyn Winn: 2-for-4, 2 RBI
  • Leo Bernal: 1-for-5, 1 HR, 1 RBI
  • Kyle Leahy: 3.0 IP, 0 ER, 2 H, 0 BB, 4 K

White Sox Standouts

  • Randal Grichuk: 1-for-4, 1 HR, 2 RBI
  • Sam Antonacci: 2-for-4
  • Hagen Smith: 2.0 IP, 0 ER, 0 H, 3 K
  • Bryan Hudson: 1.0 IP, 0 ER, 1 K (save)

What's Next for St. Louis

The Cardinals will look to bounce back quickly as the regular season continues. Saturday's loss was a winnable game — the offense showed up, Kyle Leahy gave the team a solid foundation, and Chicago needed a major meltdown inning to flip the result. The bullpen, particularly Hjerpe's outing, is the storyline to watch heading into the next series. St. Louis will need its relievers to be sharper if the club is going to protect leads down the stretch of the 2026 regular season.