For the third time in two days, the Cardinals loaded the bases against a Cubs pitcher, and this time, they came through in a big way -- with the help of one of the best bases-loaded hitters of all-time.

With no outs in the first inning of Game 1 of Wednesday’s seven-inning doubleheader, Matt Carpenter crushed his second career grand slam to give the Cardinals the early lead in an eventual 9-3 victory over the Cubs and starter Alec Mills at Wrigley Field. St. Louis fell to Chicago in Game 2, 4-2, to split the twin bill.

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There aren’t many hitters better than Carpenter with the bases loaded. His 410-foot slam to center field brought his career bases-loaded average up to .500, but when he came to the plate with the bases loaded again in the sixth inning, that average dropped back down to .491 (28-for-57) when he struck out looking on a 96 mph fastball on the outside edge of the zone from reliever Jason Adam.

Dating back to 1974 -- with a minimum of 50 plate appearances with the bases loaded -- Carpenter’s average is second in the Major Leagues to former Cardinals outfielder So Taguchi's .512 average (21-for-41).

"It’s just a confidence thing," Carpenter said. "When I get into that box with those runners out there, my game is the strike zone. It always has been. And when I get into a position where there’s nowhere for the pitcher to go, he can’t afford to walk me, I just feel really confident in those moments and have been able to have some success in it.”

Carpenter became the fifth Cardinal to hit a grand slam in the first inning at Wrigley Field, and the first to do so since Adam Kennedy in September 2008.

“Any time you do something like that, it’s just impressive,” starter Jack Flaherty said. “He’s really been able to take advantage of the situation. When he gets put in that spot, he’s been able to do damage. He’s been able to have good at-bats. He always has good at-bats, but he gets in that spot, and he executes there. He does his job.”

Carpenter’s slam represented what the Cardinals want to see out of their offense, especially the top of the lineup. Mills hit Kolten Wong to lead off the game, then Tommy Edman singled and Paul Goldschmidt walked to bring up Carpenter, who has seen time in the cleanup spot or batting fifth with shortstop Paul DeJong on the COVID-19 injured list.

Carpenter took two balls in the dirt before fouling off a 91 mph sinker on the outside part of the plate. When Mills threw the same pitch again, Carpenter jumped on it and drove it.

The top of the lineup didn’t let up after that. Wong was 2-for-2 with a walk, a stolen base and a career-high four runs scored -- on top of a defensive gem in the third inning. Edman was 3-for-4 with two RBIs and two runs scored, and Goldschmidt was 1-for-2 with two walks and an RBI.

The four-run first inning gave Flaherty a lead before he had even thrown a pitch. Ian Happ’s leadoff homer put the Cubs on the board, but Flaherty was able to work out of trouble for 1 2/3 innings. When he hit Nico Hoerner to load the bases on his 41st and final pitch, lefty Austin Gomber struck out Happ to end the inning and the Cubs’ threat.

Flaherty’s pitch count was likely right around 40 in his first start since Opening Day on July 24. He worked around two uncharacteristic walks in the second inning -- one to Willson Contreras after getting in an 0-2 count, and one to Jason Kipnis, who fell into an 0-1 count before Flaherty threw four straight balls. But Flaherty said he felt strong, and he will likely be able to extend his next start.

“I was able to get into good counts and able to get ahead," Flaherty said. "I would just say I didn’t execute once I got into those spots."

The Cardinals’ bullpen, refreshed after four relievers took the bulk of the innings on Tuesday, held the Cubs scoreless until Ricardo Sánchez gave up a two-run homer to Josh Phegley in the bottom of the seventh inning. It was the Cubs’ first hit since Happ’s leadoff home run.

“The offense was really fun to watch today,” Flaherty said. “Putting up a four-spot, that kind of gives me a little room to breathe and work on executing pitches. They didn’t stop there, though. You get four in the first, it’s easy to call it a day, but they kept going at it and put up nine runs there.”