CHICAGO — Wade Davis bent over on the mound with his head resting in his arms. The All-Star closer thought Dexter Fowler's drive was headed for the iconic scoreboard at Wrigley Field, but Leonys Martin caught the ball on the warning track in centre field.

Such is life these days for the rolling Chicago Cubs.

Jason Heyward hit a tiebreaking RBI single in the seventh, Fowler's bid for another big homer came up just short and the Cubs swept the St. Louis Cardinals with a 4-3 victory on Sunday.

"Just an intense, intense baseball game," Cubs manager Joe Maddon said.

Ben Zobrist drove in two runs and Kyle Schwarber hit his 27th homer as the NL Central-leading Cubs closed out a 6-3 homestand with their sixth consecutive victory. They stayed four games ahead of Milwaukee and increased their advantage over third-place St. Louis to six games.

Pedro Strop (5-4) worked a rocky seventh for the win and Davis got his 31st save in 31 chances. The right-hander also saved Saturday's 4-1 win.

"It seems like we're competing at a pretty good level," Davis said.

Chicago led 3-0 before Fowler hit a tying three-run homer off Jose Quintana with two out in the sixth, silencing the crowd of 37,242 on a warm, sunny day. The inning began with a double for Matt Carpenter that eluded a lunging Schwarber in left.

Fowler got one last chance to hurt his former team in the ninth. With a runner on first and two out, he put a good swing on a full-count pitch from Davis, but Martin tracked it down.

"I definitely sat back in my seat when I heard it get hit," Schwarber said. "But then we took a look at the wind and saw it was blowing in and we were able to make the catch there."

St. Louis went 1 for 9 with runners in scoring position and left 11 runners on base in its fourth loss in five games, damaging its chances of making the playoffs. Lance Lynn lasted just four innings, allowing five hits and three runs.

"We got beat this series. They beat us," Lynn said. "We didn't give away games, we got beat. So we've got to win the next one and the next and the next one and the next one and hope that these guys don't do that and the wild-card teams don't do that."

The Cubs' winning rally began when Anthony Rizzo was grazed on his sleeve by a pitch from Tyler Lyons (4-1). The play was originally ruled a ball, but then was overturned by a replay review.

Rizzo advanced to second on Javier Baez's pinch-hit single and took third when Ian Happ beat out a potential double-play grounder. Heyward then hit a two-out liner into left field against Matt Bowman, making it 4-3.

"You take any win you can get, but today was great to find a way to get it done with a close game," Heyward said.

St. Louis put runners on second and third with two out in the sixth, but Carl Edwards Jr. struck out Randal Grichuk to end the inning. Brian Duensing fanned Carpenter with the bases loaded for the final out of the eighth, punctuating the big pitch with an emphatic fist pump.

SITTING OUT

Chicago played without catcher Willson Contreras, who served a one-game suspension for his confrontation with umpire Jordan Baker in the fifth inning of Friday's 8-2 win in the series opener. Contreras was originally suspended for two games, but the punishment was reduced after he appealed.

TRAINER'S ROOM

Cardinals: RHP Adam Wainwright (right elbow impingement) faced hitters before the game and said he was ready to come off the disabled list. Manager Mike Matheny liked what he saw but wasn't ready to commit to a timetable for Wainwright's return. "We haven't really talked about that yet," Matheny said. Wainwright, who was placed on the DL on Aug. 18, said he probably will pitch out of the bullpen initially when he returns. ... 2B Kolten Wong returned to the lineup after being sidelined by back spasms. Wong left in the seventh inning of Friday's 8-2 loss to the Cubs and rested on Saturday.

Cubs: There was no word on the next step for RHP Jake Arrieta (right hamstring strain), who threw 42 pitches in a bullpen session on Saturday. But he has been ruled out for Chicago's two games at Tampa Bay this week.

UP NEXT

Cardinals: Following an off day, RHP Jack Flaherty (0-1, 6.08 ERA) makes his fourth major league start Tuesday night at Cincinnati. RHP Jackson Stephens (2-0, 2.38 ERA) pitches for the last-place Reds in the opener of a three-game series.

Cubs: Maddon returns to Tampa Bay when the Cubs begin a two-game set against the Rays on Tuesday night. Maddon managed Tampa Bay for nine years before he left after the 2014 season. "I'm really honestly looking forward to it," he said. "There's so many friends in that building."

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Jay Cohen can be reached at https://twitter.com/jcohenap

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