CINCINNATI -- The St. Louis Cardinals needed this one.

Randal Grichuk hit a two-run homer and Kolten Wong added a solo shot, helping the Cardinals avoid the sweep with a 5-2 victory over the Cincinnati Reds in the finale of a three-game series Sunday afternoon at Great American Ball Park.

The Cardinals lead by 1 1/2 games in the battle for the second wild-card spot in the National League. Their closest pursuers, the New York Mets, played later Sunday night.

Sunday's win snapped a three-game losing streak for St. Louis, which has lost seven of 12.

"Whenever you have a string of games that you've lost, you look for things that can go your way," manager Mike Matheny said. "Wins fix everything."

The Reds suffered what might be a significant injury on Sunday when center fielder Billy Hamilton left in the third inning with a strained left oblique. He was replaced by Tyler Holt.

"It is an oblique and that strikes fear into everybody," said manager Bryan Price. "I don't expect to see him play for the next two or three days."

Cardinals starter Carlos Martinez (13-7) allowed two runs over seven innings on Sunday. He fanned six, but walked five.

"He's going to be careful with certain guys," Matheny said. "When he's feeling good with his sinker, I think he'll pitch tough all the way through. Later in the game, he got a little tired."

Seung Hwan Oh, who took the loss in the series opener, pitched a scoreless ninth for his 15th save.

"He's been great," Matheny said. "Continues to make good pitches. He gave up a couple hits the other night, but that doesn't even faze what we think of him. He's a top-tier pitcher."

St. Louis (71-64) extended its franchise-record streak by homering for a 23rd straight game when Grichuk belted a two-run shot in the second inning off Reds starter Tim Adleman.

Grichuk's 21st homer this season put the Cardinals ahead 2-0.

"The pitch got too much of the plate," said Adleman. "Maybe in another park it doesn't go out. Outside of a few pitches, I did a pretty good job of minimizing damage. I wasn't in a lot of jams today."

Only the San Diego Padres have a longer homer streak this season after homering in 25 straight games.

St. Louis increased its lead when Wong belted a solo shot, his fourth, to make the score 3-0 in the fifth.

"A curve over the plate," said Adleman. "You have to tip your hat. He did what he was supposed to with it."

Adleman (2-3) pitched well, aside from the two homers. He gave up four hits and three runs with a walk and six strikeouts over five innings.

The Cardinals led 5-0 in the sixth when the Reds loaded the bases with one out. But Martinez got Ramon Cabrera to ground into an inning-ending double play.

The Reds broke through in the seventh on pinch-hitter Ivan DeJesus Jr.'s RBI double and a run-scoring single by Holt. Those two runs ended the afternoon for Martinez.

Cincinnati loaded the bases against left-hander Zack Duke, but Holt was thrown out by Brandon Moss attempting to score on a shallow fly ball to left field for an inning-ending double play.

Price said the Reds wanted to be aggressive there with two outs.

"Offensively, we're down by three runs and you think you're going to be conservative, but you still have to score runs," he said. "Moss makes a nice play. We had to take a chance with two outs."

St. Louis turned four double plays on Sunday.

"On a day, too, when he was struggling to put together the at-bat he wanted to," said Matheny, of Moss. "Big play. Nice tag by Yadi (Molina). Got us out of a tough jam."

NOTES: The St. Louis Cardinals reinstated C Brayan Pena, who was on the 60-day disabled list with left knee inflammation. They also purchased the contract of C Carson Kelly from Triple-A Memphis, designated for assignment INF Dean Anna and transferred RHP Seth Maness to the 60-day DL. ... Cardinals RHP Mike Leake threw a bullpen on Sunday in Cincinnati and could start on Tuesday or Wednesday. Leake's been on the DL since August 22 with shingles. ... Reds 2B Brandon Phillips missed his second straight game with a sore left foot. ... Cincinnati selected the contract of INF Hernan Iribarren from Triple-A Louisville and designated RHP Daniel Wright for assignment.