CINCINNATI (AP) Rookie Randal Grichuk knew that in homer-friendly Great American Ball Park, all it takes is one decent swing to end a game.
Matt Carpenter tied it with a solo homer in the eighth, and Grichuk connected in the 13th inning, rallying the St. Louis Cardinals to a 4-3 victory over the Cincinnati Reds on Wednesday night.
Grichuk was moved up to second in the Cardinals' struggling batting order. He doubled home a run in the sixth inning and hit his 15th homer in the 13th off Dylan Axelrod (0-1), Cincinnati's eighth pitcher.
He knew the ballpark's reputation for yielding homers that would be outs in most other places.
''You know the ball flies here,'' Grichuk said. ''It's in the back of your mind.''
So far, Grichuk has shown a propensity to hit balls hard and strike out a lot.
''Two big swings for us,'' manager Mike Matheny said. ''He's got the potential. You might see some swings-and-misses sometimes, but you also see what he does tonight.''
Seth Maness (4-1) gave up a pair of walks in two innings, completing an impressive night by the bullpen. Cardinals relievers blanked the Reds over the final eight innings.
''The way they've been throwing the ball this year, we know that if we can scratch a few runs - not many - we've got a chance to win,'' Carpenter said. ''Today was a good example of that.''
Matheny changed the batting order - Grichuk went from batting eighth on Tuesday to second - to try to spark his struggling offense, but the Cardinals didn't get much going until late in the game.
Left-hander David Holmberg allowed two runs, including Grichuk's RBI double off the top of the wall in center that cut it to 3-2 in the sixth.
Carpenter tied it with a homer in the eighth off J.J. Hoover, only the third that the reliever has allowed this season. It was Carpenter's fifth homer in his last six games.
The Reds strung together walks and infield hits while scoring three times off Carlos Martinez.
They loaded the bases in the third with a walk, an infield single and a fielding error by shortstop Jhonny Peralta. Brayan Pena's opposite-field double landed just inside the left-field line and made it 2-0.
The Reds loaded the bases again in the fourth with a pair of walks - one to Holmberg - and Brandon Phillips' single just out of the reach of second baseman Kolten Wong. Todd Frazier's soft groundout got in another run.
The Cardinals have played 15 extra-inning games, going 7-8. Their longest was an 18-inning loss to the Mets. The Reds have played 13 extra-inning games, going 4-9. They've gone as long as 13 innings five times.
Grichuk extended his hitting streak to eight games. Stephen Piscotti's streak ended at eight games. Jason Heyward's streak ended at seven games. ... Phillips extended his hitting streak to six games. Jay Bruce's streak ended at six games.
Cardinals: Yadier Molina got hit in the facemask by Phillips' foul tip in the fourth inning. Phillips checked to see if the catcher was all right as he shook off the hit.
Reds: LH Sean Marshall threw off a bullpen mound for the first time since surgery on May 20 to remove scar tissue in his pitching shoulder. He'll throw every three days.
Cardinals: Michael Wacha (12-4) has won both of his starts against the Reds this season, allowing only two runs in 13 1-3 innings.
Reds: Michael Lorenzen (3-6) tries for his first win since June 21. He's 0-4 in his last six starts and has been hit hard in his last three, giving up 17 runs in 13 innings.
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