PITTSBURGH -- The Pittsburgh Pirates finally found a way to beat Johnny Cueto -- watch him get hurt.
The Cincinnati right-hander, who is 12-4 in his career against Pittsburgh, left the game in the fifth inning with a strained right triceps and the Pirates went on to post a 3-1 victory by scoring two runs off the Reds' bullpen.
Cueto won 19 games last season in helping the Reds win the National League Central. He was their opening day starter this season and has gone 1-0 with a 2.60 ERA in three starts.
Cueto threw a first-pitch strike to Travis Snider in the fifth after striking out Pedro Alvarez to start the inning. A Reds trainer came to the mound and briefly massaged Cueto's upper right arm before they walked off the field together.
"I believe when I threw a changeup to Alvarez that I felt something in my arm," Cueto said. "It's disappointing. I felt really good. I thought I was pitching really good and I wanted to stay in that game."
The Reds plan to fly Cueto back to Cincinnati on Sunday morning to be examined by team doctors. Manager Dusty Baker is optimistic that the injury is not severe.
"The good thing is that it's not the elbow and it's not the shoulder," Baker said. "It's in the belly of the triceps."
Cueto allowed one run and two hits in 4 1/3 innings with one walk and three strikeouts. He has allowed just seven earned runs in his last seven starts at PNC Park.
Starling Marte's two-out RBI single in the fifth off Alfredo Simon (0-1), who relieved Cueto, broke a 1-1 tie. Jose Tabata added a run-scoring double off J.J. Hoover in the seventh.
Simon gave up back-to-back singles to Snider and Clint Barmes. Simon temporarily escaped trouble by getting pinch-hitter Josh Harrison to fly out before Marte ran his hitting streak to seven games by lining his single to center field.
Pirates starter Jeff Locke (1-1) got through five shaky innings, allowing one run, for his second career victory in nine decisions. He gave up four hits and four walks with no strikeouts.
"I had a hard time trying to find the strike zone," Locke said. "I got them to hit some balls on the ground when I needed to and I was fortunate to have some good defense behind me."
Pirates manager Clint Hurdle said, "He competed and somehow he was able to get the big outs when he needed them."
Jason Grilli worked a scoreless ninth for his fifth save in as many opportunities, staying perfect as the replacement for All-Star closer Joel Hanrahan, who was traded to Boston in December. Mark Melancon, acquired in the Hanrahan trade, set down Cincinnati in order in the eighth and has not allowed a run in seven games and seven innings this season.
Justin Wilson did not give up a run in a 1 2/3 innings after relieving Locke to start the sixth and Jared Hughes retired the only batter he faced.
"I'm not counting the saves," Grilli said. "Everybody is doing their job and there is a lot of confidence in our bullpen right now."
Cincinnati lost its fourth straight game and Pittsburgh won for the fourth time in five games since starting the season 1-5.
Cincinnati's Zack Cozart opened the scoring in the third with a one-out home run to left, his third homer of the season. Cozart had three hits, including a double.
The Pirates answered with a run in the fourth. Andrew McCutchen drew a two-out walk and scored on Garrett Jones' double to the gap in left-center field. Jones had two hits and is 7-for-14 in his last four games.
NOTES: Cincinnati second baseman Brandon Phillips missed the game for what Baker termed a "family matter." Phillips might also miss Sunday's finale of the three-game series. He hit two home runs in the Reds' 6-5 loss on Friday night to the Pirates and is hitting .318 with four home runs and 10 RBI in 10 games this season. Utility infielder Cesar Izturis started in Phillips' place and wen 1-for-3 with a walk. ... Pittsburgh left-hander Wandy Rodriguez will miss his scheduled start Sunday against Cincinnati because of a strained left hamstring. Rodriguez was injured in his previous start on Monday at Arizona and forced to leave the game in the third inning. He is expected to avoid the disabled list and return to the rotation on Friday to face Atlanta. Right-hander Phil Irwin is expected to be recalled from Class AAA Indianapolis and start Sunday in what would be the 26-year-old's major-league debut. Irwin has won his lone start for Indianapolis this season, giving up one run in six innings for a 1.50 ERA. ... Right-hander Mat Latos (0-0, 4.05) will start Sunday for Cincinnati. He is 4-0 with a 2.11 ERA in seven career starts against the Pirates. ... Pirates left-hander Francisco Liriano, who has been out since the start of the season with a broken right upper arm, will begin an injury rehabilitation assignment with high-Class A Bradenton on Monday. Liriano is scheduled to pitch three innings and will be on a 50-pitch limit. ... Right-handed reliever Jose Contreras, signed by the Pirates to a minor-league contract during spring training, is scheduled to follow Liriano and pitch two innings. Contreras underwent Tommy John reconstructive elbow surgery last June.