CINCINNATI (AP) -- Even when things go horribly wrong on the road, the St. Louis Cardinals can always count on one soothing stop. No matter how deep their slump, it'll end in Cincinnati.
Matt Carpenter broke his 0-for-23 slump with a bases-loaded double during the decisive rally, and the Cardinals ended a tough trip on the upswing by beating the Reds 15-2 on Sunday.
The Cardinals went 3-8 on a trip that included seven straight losses - four of them in Pittsburgh, allowing the Pirates to overtake them for the NL Central lead. On their final stop, an offense that couldn't do much of anything found a little bit of everything.
''Offensively, we did a terrific job,'' manager Mike Matheny said. ''We had a little bit of everything - some power, some good situational hitting, made the (defensive) plays.''
It's been like that against the Reds lately.
St. Louis took two of three at Great American Ball Park and has won its last six series against Cincinnati, its best such stretch against the Reds since 2003-04. The Cardinals lead the season series 8-4.
''Some teams you play better than others, but they've got our number for sure,'' said Reds starter Mike Leake (10-5), who gave up a season-high seven runs. ''They play us tough. It's on us to try to figure them out because they've got us figured out for the most part.''
The Cardinals scored their most runs against Cincinnati since 1993. They've scored at least 10 runs against the Reds in four games this season, the first time they've done that since 1980.
Carpenter's two-run double off the wall completed a five-run rally in the sixth against Leake and two relievers, setting up another blowout.
''It's a great feeling,'' Carpenter said. ''It's even better that we come back and win the series in a convincing fashion. It was fun to join in on the action.''
Matt Adams, David Freese and Tony Cruz homered for the Cardinals, who have scored 13, 13, 3 and 15 runs in their last four games.
St. Louis finished with 19 hits and a season high in runs. Every starter except Lance Lynn drove in at least one run.
Lynn (13-5) allowed four hits in eight innings, including Zack Cozart's two-run homer. Lynn struck out a season-high 11 and joined Adam Wainwright as 13-game winners in a rotation that has the NL's third-best ERA.
''I had pretty good command of all four pitches, and I was able to use all of them on both sides of the plate,'' Lynn said. ''That makes it a lot easier to pitch. Between my last three starts, I've had the best stuff I've had all year. "
The Reds have dropped seven of nine, leaving the defending NL Central champions marooned in third place.
The Cardinals scored in the first inning of all three games of the series. They scored four off Bronson Arroyo on Friday night, one on Saturday and four more on Sunday off Leake, who had allowed a total of four runs in his last three starts combined.
Matt Holliday and Freese had RBI doubles, and Adams hit a two-run homer - his first since July 6 - for the 4-0 lead only 19 pitches into the game. Holliday improved to 9 for 20 career off Leake.
The Cardinals sent 10 batters to the plate for five runs in the sixth, aided by a pair of errors. They opened the inning with five consecutive hits, and Carpenter's two-run double off Logan Ondrusek made it 9-2 and gave the second baseman relief from his personal slump.
''At that point, I was so relieved to just put the barrel of the bat on the ball that I didn't care what happened,'' Carpenter said.
The Cardinals hit only nine homers in July, including one after the All-Star break. They had six in three days at Great American Ball Park.
Reds third baseman Todd Frazier went without a hit for his ninth straight game, leaving him in an 0-for-28 slump. It's the longest by a Reds player since Drew Stubbs went 0 for 32 midway through last season.
Notes: The Cardinals play 17 of their next 24 games at Busch Stadium. They open a 10-game homestand on Monday against the Dodgers, with Wainwright trying for his 14th victory. ... The Reds are off on Monday before resuming their homestand with a pair of games against the Athletics. ... Cardinals OF Carlos Beltran got a day of rest. ... Reds LH reliever Sean Marshall and RH starter Johnny Cueto still haven't resumed throwing. Marshall, on the DL since May 24 with a sore left shoulder, had a setback before the All-Star break. Cueto has been sidelined since June 5 with a strained muscle in the back of his shoulder.
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