"Everything kept getting sharper," manager Joe Maddon said. "We needed him to go more deeply in the game. And he did."
Quintana (9-6) allowed two runs and six hits, struck out six and walked four in his first start since July 10. The left-hander also matched his career high with 121 pitches after he got an extended break to work with pitching coach Jim Hickey on his changeup and get over some shoulder fatigue.
"We worked on that (changeup) the last couple starts and the last couple bullpen sessions," Quintana said through a translator. "It was more just having the confidence to throw it, not so much the grip, but it was something I felt like I was able to use in certain spots."
Kyle Schwarber hit a tiebreaking solo homer off Mike Mayers (2-1) with two out in the sixth inning, and the Cubs broke it open with three runs in the eighth. The NL Central leaders took three of five from the Cardinals in their first series after the All-Star break and moved 3 1/2 games ahead of second-place Milwaukee.
Carpenter's homer streak ended at six games, a single-season record for St. Louis. The infielder went deep six times in the first four games of the series, including three homers in Friday's 18-5 victory.
Carpenter ended his streak of 12 consecutive hits for extra bases when he led off the game with a bunt single. Third baseman Kris Bryant joined the Cubs' outfielders during Carpenter's at-bat, and Carpenter responded with the bunt to the left side.
"What a teammate," manager Mike Shildt said. "He goes out and he's clearly on a streak of consecutive games with a home run and in the first inning he's gonna lay down a bunt because that's what the opposition gives us."
Quintana intentionally walked Carpenter with runners at second and third in the second inning before striking out Molina looking.
Quintana struck out Carpenter swinging with one on after Yairo Munoz hit an RBI double in the fourth.
"I'm glad the manager had faith in me in a tight game to go out there and go seven innings," Quintana said.
Carpenter popped out with two on in the ninth against Randy Rosario.
"He was good super good, had all his pitches going, everything working in a tight ballgame," Shildt said. "I made a decision to hit for him. Different decision, different ballgame."
HE SAID IT
"I don't think it's helped them a whole lot in this series. Unless they can put someone in the bleachers," Shildt said about the Cubs playing four outfielders against Carpenter.
ON THE MOVE
Cardinals: RHP Luke Weaver, who was the 26th man for Saturday's doubleheader and started Game 1, returned to the minors. He is expected to return next weekend to make a start.
Cubs: RHP Dillon Maples was optioned to Triple-A Iowa.
Cardinals: INF Jedd Gyorko (illness) is feeling much better after sitting out Saturday's doubleheader, Shildt said. Gyorko grounded out as a pinch hitter with two on in the sixth inning and stayed in the game.
Cubs: RHP Yu Darvish (right elbow impingement and inflammation) threw from 135 feet on flat ground and could throw off a mound soon. He has been on the disabled list since May 23. "Just making an educated guess, you can't be overly reliant on somebody who hasn't been able to be healthy and perform this year at the same time," president of baseball operations Theo Epstein said. "You track the rehab closely because you have to try to anticipate what he might be able to give you. Today was his best day in a long time. He threw really well and felt really good." . LHP Drew Smyly (Tommy John surgery) threw a simulated game and is expected to throw another one Thursday.
Cardinals: RHP Daniel Poncedeleon will make his major league debut Monday at Cincinnati. He underwent surgery in 2017 to relieve pressure around his brain after he was hit in the head by a line drive while pitching for Triple-A Memphis. RHP Luis Castillo (5-8, 5.49 ERA) is set to start for the Reds.
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