CHICAGO -- Rookie Alex Reyes is enjoying his time pitching in an important role for a team trying to reach the playoffs.

He came up big in pivotal moments on Saturday as the visiting St. Louis Cardinals breezed to a 10-4 win over the National League Central champion Chicago Cubs.

With a runner on third, Reyes struck out 2015 Rookie of the Year Kris Bryant in the fourth inning to preserve the Cardinals lead. Reyes escaped trouble and St. Louis scored six runs in the first three innings.

The Cardinals trail New York and San Francisco by one-half game in the NL wild-card race.

"Anytime I get the ball I like to go out there and have fun," said Reyes (4-1), who scattered six hits and three walks in five innings. "Being able to be out there for a big win, help the club win was absolutely fun."

Reyes gave up a season-high three runs while throwing 115 pitches, the most for a St. Louis rookie since 2002. Three of his four victories have been against the Cubs.

"He did a nice job of managing the damage," manager Mike Matheny said. "When you have 71 pitches after three (innings), you typically got a lot more on you than the three runs they had."

Stephen Piscotty homered, Yadier Molina drove in four runs and Randal Grichuk plated three for the Cardinals, who have won five of its last seven games.

"A good offensive day all the way around," Matheny said.

The Cardinals improved to 6-3 at Wrigley Field and 9-9 overall against the Cubs this season.

"They're obviously the best team in the league," Molina said. "We respect that, but at the same time, we come here thinking about winning."

The Cubs saw their four-game winning streak end. They remain stuck on 98 victories and tied for a franchise-record 56 home wins. Chicago last won 99 games in 1935, when it reached 100.

"Our starter had a tough day today. Otherwise, we did some nice things," manager Joe Maddon said.

Jason Hammel (15-10) struggled in his latest audition for a Cubs playoff roster spot. He allowed six runs and six hits in 2 1/3 innings, tying his second-shortest outing of the season. His ERA rose from 3.56 to 3.83. The Cubs used seven relievers.

"I felt alright, for the most part," Hammel said. "It was the slider that beat me today. In the first inning, the three hits were check swings, sliders that had no depth. They did a good job of putting the ball in play."

The Cardinals scored four runs with two outs in the first inning on Molina's two-run double and Grichuk's two-single.

Ben Zobrist's two-run triple cut the deficit to two in the bottom of the first, ending Reyes' scoreless streak of 11 1/3 innings. But Piscotty's 22nd home run made it 5-2 in the second.

Dexter Fowler's RBI double brought the Cubs back to within two in the bottom of the second. Reyes left two on in the inning.

"He's a young guy, but at the same time he looks like a veteran," Molina said. "He gets on the mound and he's not scared. He's just trying to figure it out and make pitches."

The Cardinals padded their lead to 9-3 with three runs off Hector Rondon in the seventh. Matt Adams hit an RBI double and Molina added a two-run single.

"We are a good offensive team." Molina said. "It's been a difficult year for us, up and down, but right now we got a good win and a lot of base hits. Hopefully, we can continue it.

Chicago's Willson Contreras hit his 11th home run in the ninth.

The Cubs secured home-field advantage during the NL playoffs when the Washington Nationals lost to the Pittsburgh Pirates on Friday night, after Chicago beat the Cardinals 5-0 in the series opener.

NOTES: Cardinals OF Matt Holliday (broken right thumb) felt sore Saturday after he took batting practice Friday. He will see a specialist Monday before possibly hitting again, manager Mike Matheny said. ... Cardinals OF Kolten Wong was out of the lineup after he face-planted trying to make a catch in center field Friday. ... Cardinals SS Aledmys Diaz (arm soreness) returned to the lineup Saturday after missing two games. He has been dealing with arm soreness after he returned from the disabled list Sept. 11 for a right thumb fracture. ... Cubs LF Jorge Soler (tight side) is back in the lineup after not starting since Sept. 16. He entered Friday's game against the Cardinals as a pinch hitter. ... Cubs RHP Pedro Strop (left meniscus tear) said he was excited Friday during his first appearance since landing on the disabled list Aug. 11. The Cubs plan to pitch him about three times during the final week of the regular season. Strop said he will have to pitch on back-to-back days. ... The Cubs' scheduled rotation for their four-game series against the Pirates starting on Monday is: RHP Kyle Hendricks on Monday, RHP John Lackey on Tuesday, RHP Jake Arrieta on Wednesday and a bullpen day on Thursday. ... Cardinals pinch hitters lead the majors with a .329 average and 74 hits.