Beltran also had three hits as St. Louis won for the seventh time in eight games and improved to a major league-best 14-7 on the road. The Cardinals went 5-1 on a six-game swing to Milwaukee and Chicago, with the lone loss coming Tuesday in their first game of the season against the last-place Cubs.
The Cardinals trailed 4-3 before Beltran singled in Matt Carpenter in the seventh, and Jay drove in Yadier Molina with a tiebreaking single against Michael Bowden (1-2) in the eighth. Each rally featured a costly mistake by the Cubs, with Carpenter moving to third on an error by right fielder Nate Schierholtz and Molina advancing to second on a wild pitch.
Anthony Rizzo had three hits and Schierholtz hit a two-run double for Chicago, trying for its second three-game winning streak this season. Instead, the Cubs finished a 4-6 homestand.
Chicago had 11 hits but grounded into four double plays, one in every inning from the fifth to the eighth. The last one was particularly heartbreaking, with the potential tying run on third.
Four Cardinals relievers combined for 3 2-3 innings of two-hit ball after Jake Westbrook had his worst start this season. Seth Maness (2-0) got five outs to get the win and Edward Mujica worked the ninth for his ninth save in nine opportunities.
The afternoon game on a picturesque spring day in Chicago attracted 26,354 to Wrigley Field, and fans were treated to a little bit of everything. There were a couple of adventures on the basepaths, a rarely seen 4-2-3 groundout and a bunch of singles - just three of 22 hits were for extra bases. Julio Borbon of the Cubs was called out for interference for running inside the baseline in the seventh.
Jay's sacrifice fly gave the Cardinals a 2-1 lead in the fourth inning, but the Cubs responded with three in the bottom half on two hits, a walk, an unusual carom and a perfectly placed grounder.
With no outs and runners on first and second, Schierholtz pulled a 3-2 pitch from Westbrook down the first-base line. The ball bounced off the wall in foul territory and out into right field, allowing Rizzo and Luis Valbuena to scamper home. Schierholtz moved up on a groundout and scored on Dioner Navarro's slow roller to make it 4-2.
The Cardinals had their infield in with Navarro at the plate, but Schierholtz scored easily. With Molina standing in front of the plate and pointing to first, Carpenter still came home with the throw from second, and the Gold Glove catcher made a strong throw to first to retire the lumbering Navarro.
Molina also cut down Rizzo when the big first baseman tried to steal third following his two-out RBI double in the first. But the Cardinals had their own baserunning blunder in the fifth, when Carpenter was thrown out after he made a wide turn at second on Beltran's run-scoring single.
Carpenter's gaffe became even worse when Matt Holliday followed with another single to put runners on first and second. Schierholtz then bailed out Villanueva with a nice sliding catch in right to retire Craig and end the inning.
Westbrook allowed four runs - three earned - and nine hits in 5 1-3 innings, increasing his ERA from 1.07 to 1.62. He had allowed just four earned runs all year.
Carlos Villanueva pitched 6 2-3 innings for Chicago and was charged with three runs and seven hits.
NOTES: Schierholtz made another diving catch in the ninth. ... Cubs RHP Kevin Gregg has converted each of his five save opportunities since he was promoted from Triple-A Iowa on April 16, seizing the vacant closer role that's already been held this season by Carlos Marmol and injured RHP Kyuji Fujikawa. ''Gregg's our closer. That's pretty much the way it is right now,'' manager Dale Sveum said. ''He's obviously earned it. There's a bigger sample out there now to know that.'' ... Cubs 2B Darwin Barney and LF Alfonso Soriano got the day off. ... The Cardinals are off Thursday, then host the Rockies on Friday. RHP Shelby Miller (4-2, 1.96 ERA) faces Colorado RHP Jon Garland (2-2, 4.65) in the opener of the weekend series. ... Chicago begins a three-game series at Washington on Friday. RHP Jeff Samardzija (1-4, 3.09) is scheduled to face Washington LHP Ross Detwiler (1-3, 2.50).
Link to box score: St. Louis 5 at Chicago 4
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