"Eight great innings and unfortunately it will be remembered for Jon Jay hitting a double and then the Cardinals doing some good situational offense," manager Bryan Price said after St. Louis won 2-1 to sweep a three-game series Sunday night.
"That's what's unfortunate, to sit there and talk about what the Cardinals did right and we didn't."
Leake (0-1) gave up both runs and four hits in eight innings for the Reds, who have totaled four runs during a four-game losing streak. Brandon Phillips had two hits and an RBI and Joey Votto singled in his first two trips.
"You're not going to score runs every day," Leake said. "Wainwright's a tough guy to score runs on, so you can't necessarily expect runs on guys like that.
"You've got to keep games close and unfortunately it was a 2-1 game."
Leake got through seven innings on just 76 pitches, the only damage on Matt Carpenter's fifth career leadoff homer.
"Out of the gate, man that's tough," catcher Tucker Barnhart said. "But he righted the ship really quick. That's Mike, he throws a bunch of strikes, he pitches to contact and he kept us in the game all night."
Jay doubled to open the eighth, advanced on a fly out and scored without a play on Kolten Wong's sacrifice fly to left.
Matt Carpenter singled for his eighth multihit effort this season as the Cardinals won their fifth straight.
Wainwright (2-1) gave up one run and seven hits with four strikeouts and two walks, improving to 3-0 against the Reds the last two seasons. Leake was more economical, throwing 86 pitches with 66 for strikes.
Reds hitters had a frustrating night against Wainwright.
"He wasn't as overpowering, his curveball wasn't as hard, his velocity wasn't as high, but he managed the strike zone extremely well and made all the big pitches that he needed to make," Price said. "We just weren't able to get anything done."
Cincinnati loaded the bases with two outs in the eighth against Wainwright before Zack Cozart grounded into a forceout. Cozart is 0 for 6 with runners in scoring position.
Leake and Wainwright combined for 25 consecutive outs before Carpenter ended Leake's run of 15 in a row with a one out-single in the sixth that hiked his average to .400. Carpenter has six consecutive multihit games and nine in the first 11.
Barnhart's two-out single in the seventh halted an 0-for-12 stretch against Wainwright with two strikeouts and two balls hit out of the infield.
Carpenter's fifth career leadoff homer to straightaway center, tied for third-most in franchise history, gave the Cardinals the early lead. It was his first leadoff homer since July 22, 2014, against Tampa Bay.
Three straight Reds reached with two outs in the third and Phillips' bloop single tied it, ending Wainwright's run of 19 2-3 consecutive scoreless innings against Cincinnati.
Reds: C Devin Mesoraco may be close to returning to the lineup. He missed his sixth straight start with a left hip injury but was available Sunday to pinch hit. ... OF Billy Hamilton was much improved from a groin injury beating out an infield hit Saturday and though he didn't start also was available.
Cardinals: Matt Holliday started in LF a day after coming out with back tightness after scoring in the first inning. He has an 11-game hitting streak after singling in the first.
RUN TO GLORY
Before the game, Go! St. Louis Marathon women's winner Andrea Karl ran through finishing tape on the warning track in honor of the victory first granted to an imposter recently.
Reds: Anthony DeSclafani allowed two hits in seven scoreless innings his last time out at Chicago and faces the Brewers for the second time.
Cardinals: The Cardinals are off Monday before starting a six-game trip. Lance Lynn (1-1, 1.64) gets the call Tuesday at Washington.