CINCINNATI — Bronson Arroyo’s pitches were moving so unpredictably to the first few batters that catcher Ryan Hanigan went out to the mound with a funny suggestion.

“He said, ’You’re so bad today, I’m going to set (the mitt) down the middle and you throw it,”’ Arroyo said.

No need to get so drastic.

The right-hander quickly got things under control and pitched into the eighth inning for his fifth straight win, leading the Cincinnati Reds to a 4-0 victory over the Pittsburgh Pirates on Wednesday night.

Arroyo (5-2) allowed five hits — all singles — in 7 2-3 innings. He walked Aki Iwamura to start the game, then managed to get his pitches going where he intended.

“Sometimes you feel funky out there,” said Arroyo, who also had trouble with his control warming up. “I couldn’t get a groove going. I got out of that (first inning) and my command came back. I kind of got on a roll.”

He started fading in the eighth on a warm, muggy night, leaving after his 113th pitch. Daniel Ray Herrera pitched out of a bases-loaded threat, striking out Garrett Jones on a 66 mph screwball to end Pittsburgh’s last chance.

Orlando Cabrera drove in two runs, and Miguel Cairo had a solo homer off Ross Ohlendorf (0-3), who was in trouble most of his six innings. The right-hander gave up eight hits and walked five, also struggling at the outset.

Ohlendorf missed roughly a month because of back spasms. He’s 0-3 since his return from the disabled list and still trying to get back in form. He walked three in the first two innings, setting himself up for a tough time.

“I’m definitely not pitching like I’d like to,” Ohlendorf said. “After the first two innings, I felt a lot better. I was able to relax and trust my stuff more. I was nibbling in the first two innings.”

Manager John Russell liked the way Ohlendorf pitched after those ragged, opening innings.

“I think it’s a step in the right direction,” Russell said. “Once he picked up the tempo, he threw the ball pretty well. I hope he builds off it and has confidence when he takes the mound.”

The Reds have won eight of 12, jostling with the St. Louis Cardinals for the top spot in the NL Central. They began the day with identical records.

Pittsburgh has been shut out seven times, most in the NL. Things don’t get any easier for the Pirates in the finale of the four-game series — they face Johnny Cueto, who threw a one-hitter for a 9-0 win in Pittsburgh on May 11.

The Pirates have scored the second-fewest runs in the NL. They got only one runner to third base against Arroyo, who tends to be streaky. He’s on quite a tear now. The right-hander is 5-0 in his last six starts, allowing only 13 earned runs.

Second baseman Brandon Phillips made two impressive plays behind Arroyo, ranging far to snag a grounder and start a difficult double play in the sixth, then leaping well off the ground to snag Lastings Milledge’s liner in the seventh.

“I’m still surprised I got up that high,” Phillips said. “I felt like I was on a (basketball) court. On that one, I had time to squat and get up. I don’t think I’ve jumped that high for a ball since the minor leagues. I think that’s the highest I’ve gone.”

Arroyo’s bunt single helped the Reds load the bases with one out in the second. Cabrera hit a sacrifice fly, but the Pirates nailed Hanigan at the plate when he tried to score from second base on Cairo’s single.

Cairo hit his first homer in the fifth inning. He had only one homer last season, on Oct. 4 with Philadelphia. Cairo has four homers in the last six seasons while playing for the Mets, Yankees, Cardinals, Mariners, Phillies and Reds.

Chris Heisey’s pinch-hit homer in the eighth off Brendan Donnelly made it 4-0. The Reds have four pinch-hit homers, two by Heisey.

NOTES: Pirates 3B Andy LaRoche missed his fifth straight game with a sore back. … Reds LHP Arthur Rhodes was unavailable out of the bullpen because of a sore foot. … An estimated 650 dogs were with their owners in the stands by the right-field foul pole, part of an annual pet promotion. During the nightly “KissCam” segment, the videoboard showed a couple with their dog. The woman kissed the dog but not the man.