HOUSTON — Rookie Mike Leake was in college at this time last year.

Now he’s pitching with poise that sometimes takes years to develop.

Leake pitched seven sharp innings and the Cincinnati Reds scored three runs on a blunder by right fielder Hunter Pence to beat the Houston Astros 6-4 on Wednesday night.

Leake (2-0), who never pitched in the minors, gave up five hits and struck out five as Cincinnati won its third in a row.

“He is a quick learner,” Reds manager Dusty Baker said. “He’s very confident, but not cocky with his confidence. Like I said in spring training, he came there to make the team. He didn’t come there to attend his first big league camp, so that says a lot for his confidence and poise and his ability to learn and retain very quickly.”

Leake said he’s benefited from the leadership of Cincinnati’s veterans.

“There’s always adjustments in baseball, but these guys are helping me by bringing me along and making it easier on me,” he said. “Just treating me with respect and guiding me along slowly but surely.”

The Reds were up 2-0 in the fourth inning when Pence lost the ball in the sky at dusk with the Minute Maid Park roof open on a high fly hit by Brandon Phillips. The ball dropped just beyond his glove for an error that cleared the bases.

“It’s a play that has to be made,” Pence said. “Here, when the twilight hours are going on the balls disappear and you just have to keep going with it and try to find it. I lost it and found it late and wasn’t able to recover.”

Lance Berkman hit a two-run homer in the ninth off Nick Masset. Closer Francisco Cordero gave up Geoff Blum’s run-scoring single before retiring the last two batters with runners on first and second.

Leake, the eighth overall pick in last year’s draft, is the 21st player since the draft started in 1965 to play in the majors without spending a day in the minors.

Leake gave up a single with one out in the first inning before the Reds turned a double play to get out of that inning. The 22-year-old flew through the next few innings, retiring 10 straight. He didn’t allow another hit until a double by Pedro Feliz with one out in the fifth inning.

Pence singled before Leake walked Kaz Matsui to load the bases and send pitching coach Bryan Price to the mound for a visit with his rookie.

Humberto Quintero drove in Houston’s first run with his groundout that made it 6-1. Leake walked pinch-hitter Cory Sullivan, but was able to limit the damage by striking out Michael Bourn to end the inning.

“He got in trouble that one inning but got out of it,” Baker said. “He kept the ball down for the most part, and he battled for seven innings. Very good outing for him, but at the same time, we scored some runs.”

Orlando Cabrera singled and Ramon Hernandez doubled with one out in the fourth. Drew Stubbs walked with two outs to load the bases before Pence’s costly error made it 5-0. Scott Rolen added an RBI double off Felipe Paulino (0-3).

Bourn said he couldn’t see that ball in the outfield either and yelled to Pence to help him out.

“It’s always around the fourth or fifth inning … the sky makes it tough to see and you just hope that the situation doesn’t come up in the game,” Bourn said. “But tonight you could say it cost us the game basically.”

Joey Votto hit an RBI triple in the third. Stubbs singled to start the game, stole second and scored on Rolen’s grounder.

NOTES: Leake got his fourth career hit with a single in the sixth inning, but was thrown out when he tried to stretch it into a double. Jeff Keppinger tagged him as he slid head first toward second base. … The homer was the 315th in Berkman’s career, moving him ahead of Reggie Smith and into sole possession of fifth place on the career list for switch-hitters.