SARASOTA, Fla. — David Hernandez is making it difficult for Baltimore Orioles Manager Dave Trembley to fill out his starting rotation.

Hernandez pitched five scoreless innings Saturday in a duel with John Lackey, leading the Orioles to a 6-1 victory against the Boston Red Sox.

The competition for the fifth spot in Baltimore’s rotation remains unsettled. Hernandez, who allowed four hits, walked two and struck out six, is trying to beat out Chris Tillman and Jason Berken.

“I would say we’re going to go 15 rounds with it. We’re going to go the distance,” Trembley said. “We’ll keep running these guys out there and try to make the right decision. Guys are answering the bell, they’re making it real tough for me, and I like it.”

Lackey extended his run of scoreless innings to 13 before yielding RBI singles to Cesar Izturis and Felix Pie in the fifth. He ended with a perfect sixth.

“He gets it and throws it over the plate. We were real happy,” Boston Manager Terry Francona said. “He continues to pound the zone. He stays down and is efficient.”

Francona said Lackey also threw 15 pitches in the bullpen.

Alan Embree, who signed a minor-league contract with Boston last week, got two outs in the eighth, but allowed three runs, two hits and a walk in his spring debut.

“I think you have to back up and realize it’s his first time out,” Francona said. “Everybody else has been down here for a while and they look like it. The ball came out of his hand OK we’ve just got to get some reps under his belt.”

Boston left fielder Jeremy Hermida left with right hamstring tightness, but Francona said it was a precautionary move.

“I don’t think it was anything. It just didn’t seem like a good thing to keep him in the game,” Francona said. “He said, ‘I feel it,’ and I said, ‘That’s enough.’ “

Boston’s run came on a ninth-inning sacrifice fly by Tug Hulett.

 

RED SOX third baseman Mike Lowell said his bruised left knee felt much better one day after he fouled a pitch off it.

Lowell said the swelling had gone down but it’s still difficult to flex his leg after injuring it in the first inning of Friday’s game against Toronto.

“I feel great compared to (Friday),” he said. “The swelling under the kneecap’s a little annoying. I can’t really flex my quad, but I figure it’s gone down probably to about a quarter of what it was. So I think that’s good.”

Lowell planned to ice the knee and ride a stationary bike.

Francona said it was too early to decide if Lowell would be put on the disabled list.

“I think it’s a minor setback,” Lowell said.