CINCINNATI (AP) -- A hanging a slider, a fastball that strayed right down the middle. With no margin for error, left-hander Francisco Liriano made two of them that went a long way and decided a close game.
Zack Cozart and Todd Frazier hit upper-deck homers off Liriano, and the Cincinnati Reds moved a season-high 15 games over .500 by beating the Pittsburgh Pirates 4-1 on Monday night.
The Reds (43-28) hit four solo homers in all, extending their best start since 1995, the last time they won a playoff series.
For the Pirates, it was a wasted chance to jump ahead of Cincinnati into second place in the NL Central. And it came down to a handful of pitches.
"I made two mistakes, a hanging slider and a fastball right down the middle," said Liriano (5-3), who hadn't given up a homer this season. "You can't make those mistakes at this level."
Cozart connected off the hanging slider in the fourth and Frazier hit a first-pitch fastball in the sixth. Liriano hadn't give up a homer in his seven previous starts. He opened the season on the disabled list, recovering from a broken right arm last December.
Joey Votto and Jay Bruce connected in the eighth inning off Bryan Morris, who hadn't allowed a homer to a left-handed batter this season. Bruce has three homers during a five-game hitting streak.
"That hasn't really been a problem with him this season," manager Clint Hurdle said. "When you make mistakes against guys in the major leagues - especially in this ballpark - they're going to do damage."
Mike Leake (7-3) extended the best stretch of his four-year career, giving up six hits - including Russell Martin's RBI double - in seven innings. Leake got 13 outs off ground balls and fanned three.
The right-hander is 5-1 in his last seven starts with a 1.15 earned run average, showing why the Reds made him their first-round pick in the June 2009 draft.
"He's been doing this for three months now and building up to this," Hurdle said. "That's a guy that can pitch. That's what he's evolved into. He pitched as well as I've ever seen him."
Tony Cingrani made his first relief appearance this season and pitched out of a two-on threat in the eighth, fanning Pedro Alvarez to keep the score 2-1. Cingrani joined the rotation when Johnny Cueto went on the disabled list, and the Reds kept him around with Cueto back so they'd have another left-hander in their depleted bullpen.
Aroldis Chapman pitched the ninth for his 18th save in 20 chances, walking one and fanning two.
The Ohio River rivals have occupied the second and third spots in the NL Central most of the season, staying right behind the torrid Cardinals. The Pirates have gone 4-2 against the Reds at PNC Park, where they've won 25 games overall, tied with Cincinnati for most home wins in the majors.
It's their first visit of the season to Cincinnati. The Pirates went only 3-6 at Great American Ball Park last season, unable to take advantage of its hitter-friendly dimensions.
Liriano gave up Cozart's seventh homer in the fourth inning, extending the shortstop's hitting streak to seven games. Frazier hit his ninth homer in the sixth inning for a 2-1 lead, a drive that also landed in the upper deck in left field and was estimated at 443 feet.
Several nice defensive plays also helped to keep it close.
Starling Marte made a diving, backhand catch of Brandon Phillips' slicing line drive to left field in the third inning, forcing the Reds to strand a runner at second base. Cozart turned a couple of tough-hop grounders into outs, preventing the Pirates from threatening in the early innings.
NOTES: Marte was back in the lineup batting leadoff. He was out of the lineup the last four games with a strained left oblique. ... RH A.J. Burnett, who went on the 15-day DL last Thursday with a strained right calf, won't do much for the next three days. ... LH Wandy Rodriguez, on the DL with a sore left forearm, threw in the bullpen on Monday. He's eligible to be activated on Friday. ... Reds OF Chris Heisey started a rehab assignment at Triple-A Louisville. He's been on the DL since April 29 with an injured right hamstring. ... NASCAR drivers Bobby Labonte and Kevin Harvick threw ceremonial pitches. Hits king Pete Rose watched the game from behind home plate. He attends several games a season in his hometown.
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