PITTSBURGH (AP) -- The Atlanta Braves have hit their first rough stretch of the season.
Slumping Clint Barmes had a pair of run-scoring singles for his first two RBIs of the season, including a tiebreaking hit in the sixth inning Sunday that led the Pittsburgh Pirates over Atlanta 4-2 for their third straight win over the Braves.
"We're just not capitalizing on our opportunities offensively," Atlanta manager Fredi Gonzalez said. "We're not getting that big hit when we need it. We're not catching any breaks either, like a broken-bat hit or a pitch going to the backstop. It'll turn around, though. We're playing good baseball."
Atlanta, which has lost four of five following a 12-1 start, went 3 for 23 with runners in scoring position during the four-game series. Two of those hits came in the second inning Sunday, when Atlanta also stranded 10 runners.
Atlanta went ahead 2-0 in the second on consecutive singles by Chris Johnson, Reed Johnson, Gerald Laird and Andrelton Simmons. The Braves never scored again, and Barmes produced two big hits despite beginning the day with an .093 batting average and in an 0-for-14 slide.
After Atlanta took the lead in the second, the Pirates answered in the bottom half when Pedro Alvarez singled and scored on Russell Martin's double, and Barmes followed with a tying single.
Then in the sixth, Neil Walker singled leading off against Kris Medlen (1-2), advanced to third on Alvarez's flyout and Martin's groundout, and scored on Barmes' single to shortstop. Andrelton Simmons gloved the ball near second but couldn't get the throw to first in time as Barmes raised his average to .130 with a 2-for-3 day.
Luis Avilan threw a run-scoring wild pitch in the seventh.
"We had the matchup we wanted there in the sixth inning with Kris against Barmes, and he just hit the ball to a spot where we couldn't make a play on it," Gonzalez said. "Sometimes, it happens that way."
Medlen admitted it was a frustrating way to fall behind.
"I made a pretty good pitch, and it wound up being a little infield single that decided the game" Medlen said.
Medlen lost for first time in 29 regular-season starts in which he was given a lead. He allowed three runs and six hits in six innings with six strikeouts and one walk.
"I really haven't been swinging the bat as badly as it looks," Barmes said. "If some hard-hit balls had found some holes, then my average would be better. Still, I know it looks bad when you look at the average, and it's tough to keep grinding and having nothing to show for it."
Justin Wilson (1-0) got his first major league win by giving up one hit in 1 2-3 scoreless innings. He entered with the score tied in the sixth and induced an inning-ending double-play grounder from B.J. Upton.
Jason Grilli pitched a scoreless ninth inning. Grilli entered the season with five saves and is seven for seven in chances this year.
Wilson, Grilli and fellow relievers Jeanmar Gomez, Jared Hughes and Tony Watson combined for six scoreless innings after Jonathan Sanchez needed 74 pitches to get through three innings. Sanchez allowed two runs and four hits, lowering his ERA to 11.12 from 12.96.
"We're not getting that big hit when we need it," Braves left fielder Justin Upton said.