ST. LOUIS -- The Cardinals turned a marquee May matchup against the reigning World Series champs into a statement series at Busch Stadium. For those who may have assumed the Cubs would coast to another division title this season, the Cardinals asserted their intentions to stick around as contenders. With a 5-0 win over Chicago on Sunday, St. Louis claimed the series victory and retained its spot atop the National League Central.
The Cubs, who fell below .500 with their seventh loss in nine games, sit 3 1/2 games back.
"Any time you play a team that you think is going to be in it all the way through the end, and you can win a series, it's big," said Cardinals first baseman Matt Carpenter. "Whether it's April, May or September, you want to win all these series. They're going to be crucial. Every one of them, I think, is going to come down to a swing game like this. I'd be very surprised if anybody sweeps anybody going forward."
In front of another sellout crowd, again divided in red and blue, the Cardinals prolonged Jacob Arrieta's woes by crushing a pair of two-run homers off the right-hander. Yadier Molina went first, blasting a first-pitch fastball into the left-field seats in the second for the first of his two home runs on the day. An inning later, Carpenter finally got the better of his former Texas Christian University teammate and connected for his eighth home run of the year.

"It's not the ideal first hit I'd like to give up to him," Arrieta said, "but you've got to give him a little credit there."
Arrieta, who entered the day with a career 1.71 ERA against the Cardinals, saw his season ERA creep up to 5.44. In 44 2/3 innings this year, he's allowed eight homers -- half of his 2016 total.

"If you look at the percentage of strikes to balls and where the location was and repetition of his delivery, he was never in any trouble," Cubs manager Joe Maddon said of Arrieta. "They just hit two homers."
• Homers aside, Arrieta's start draws praise
Adam Wainwright, on the other hand, put in his best performance of the season. He did not allow a run for the first time since July 2016, and pitched a season-most seven innings. Once he worked around two baserunners in a 21-pitch first inning, Wainwright had relatively little trouble limiting a Cubs offense that was again without Kristopher Bryant and Benjamin Zobrist. Wainwright was aided by a pair of double plays.

"When you have a packed house, an over-packed house, last night and all the life today, you can't help but get sucked into that," Cardinals manager Mike Matheny said. "To see him go out there and throw seven and make the pitches when he needed to -- he had a good fastball today, his curveball was terrific -- it was just a great shot in the arm for our club, and, I think, for our fans."
MOMENTS THAT MATTERED
Long overdue: A teammate of his at TCU and a groomsmen in his wedding, Arrieta had also been a nemesis to Carpenter before Sunday. Including his first-inning groundout, Carpenter was 0-for-28 in the regular season against his longtime friend before connecting for a two-run homer that put the Cardinals ahead by four. It was no cheap shot, either. According to Statcast™, Carpenter's home run traveled 414 feet after coming off his bat with an exit velocity of 105.7 mph.
"I'm sure he's got the utmost confidence when he's facing me because he's had so much success," Carpenter said. "I just got in a good spot with a runner on first base, got a pitch elevated and was able to put a good swing on it." More >
Sweet swing: Using a pink bat on Mother's Day, Molina connected for the third multihomer game of his career and first since 2011. Molina, who had five singles in 27 career at-bats versus Arrieta, took him a Statcast-estimated 410 feet deep in the second inning. He then hit an eighth-inning solo shot off reliever Brian Duensing that traveled 412 feet. Afterward, he pointed in the stands to his mother and wife, both of whom were in attendance.

"It's special day," Molina said. "Any time you have your family here, your mom is here, she got the opportunity to see that. That's good."
The home runs pushed Molina's career hit total against the Cubs to 191, second only to Jose Pujols (196) among active players.
QUOTABLE
"It's one of the greatest rivalries in sports. Any time we beat the Cubs, especially at home, we love beating them at home here. Their fans show up in droves here. When I looked out in the bleachers early, I almost thought I was at Wrigley [Field], there were so many Cubs fans out there. They're proud of their team. They love their team. They follow them well. It was big for us to win." -- Wainwright, whose 14 career wins versus the Cubs are tied for most among active pitchers
"We would obviously like to be playing better than we are right now. I don't think there's any reason to panic. The talent we have here will correct itself and start to turn itself around. We'd like to win a few more games than we are and tighten things up a little bit, but guys are showing up ready to play and going about things the right way. We're just not getting the results we'd like." -- Arrieta, on Cubs' slow start
SOUND SMART WITH YOUR FRIENDS
The Cubs' visit to St. Louis became the most-attended three-game series in Busch Stadium III history, with a total attendance of 143,408. That included an announced attendance on Sunday of 47,925, which established a new single-game record at the ballpark.
UPON FURTHER REVIEW
With the help of replay, the Cardinals turned a nifty double play to help Wainwright through the fourth inning. Carpenter fielded Miguel Montero's sharp grounder, threw to second for the first out, and then watched as Wainwright scrambled to cover first for the double-play try. Wainwright's foot wasn't on the base when he took the throw from shortstop Aledmys Diaz, but Montero missed the bag entirely as he tried to lunge past Wainwright. Montero was initially called safe, but that was overturned after a 68-second review.

With two outs in the Cardinals' sixth, Randal Grichuk lined a ball down the left-field line and was credited with a double. Left fielder Kyle Schwarber did throw to second baseman Javier Baez, who made a swipe tag. The Cubs challenged the ruling, saying Baez made the tag in time, and after a review, the call stood.

WHAT'S NEXT
Cubs:John Lackey will open a 10-game homestand on Tuesday at 7:05 p.m. ET against the Reds at Wrigley Field. It'll be a rematch of an April 23 game between Lackey and 40-year-old Bronson Arroyo. The Reds won that game, 7-5. Kris Bryant is expected back in the lineup after not starting three straight games because of a stomach virus.
Cardinals: After an off-day on Monday, the Cardinals will continue their homestand with a two-game series against the Red Sox. This will be Boston's second visit to Busch Stadium since the two teams met in the 2013 World Series. Lance Lynn, one of 10 players on that World Series roster still with the Cardinals, will start Tuesday's series opener against Eduardo Rodriguez. First pitch is scheduled for 7:15 p.m. CT.
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