ST. PETERSBURG, Fla. — The winning pitcher was Jon Lester.

But he didn’t sound much like a winning pitcher after his performance in the Sox’ 8-6 victory over the Devil Rays last night.

The left-hander lasted only 5 1/3 innings. He gave up only four hits, but he was in and out of the strike zone all game long, losing an early two-run lead and then squandering a scary portion of a seemingly comfortable five-run advantage,

Carlos Pena took him deep for a two-run shot after a two-out walk in the first, tying the game at 2-2. And Akinori Iwamura lofted a three-run opposite-field homer on a 3-and-2 pitch in the fifth, cashing in another walk and a single, slicing Boston’s lead to 7-5.

“At times it (his command) was pretty good, at times it was really bad,” said Lester, who has a 5.67 earned-run average in six starts since being promoted from Pawtucket.

“I was inconsistent once again. We worked on some things (between starts) and tried to figure it out. I just have to go out every five days and try to get better. Luckily (last night) the bullpen picked me up great and we got a win out of it,” he said.

Manny Delcarmen (unearned run), Hideki Okajima and Jonathan Papelbon finished up with hitless relief.

Pena trade complete

The Red Sox have acquired first baseman/outfielder Chris Carter from Washington via the Diamondbacks, completing last week’s trade of Wily Mo Pena to the Nationals.

The Nationals obtained Carter from Arizona for minor-league right-hander Emiliano Fruto and then sent him to the Sox, who have assigned him to Pawtucket.

Carter, a left-handed hitter, was batting .324 with 18 homers and 84 RBI in 126 games for Tucson, the Diamondbacks’ Triple-A club. He was leading the Pacific Coast League in hits (163), tied for second in doubles (39) and was fifth in batting average.

No passed ball

Kevin Cash, who did a solid job catching Tim Wakefield’s knuckleballs Monday night in his first game replacing catcher Doug Mirabelli, had a passed ball taken away from his log yesterday.

Cash initially was charged with a passed ball when Carl Crawford struck out in the first inning. The pitch bounced off Cash’s mitt. He chased it down and threw out Crawford at first base as Akinori Iwamura, running from first base, made it to second. But upon further review, a catcher cannot be charged with a passed ball on such a play.

Cash, by the way, played for Tampa Northside Little League in the 1989 Little League World Series in Williamsport, Pa. That gives the Sox two catchers with Little League World Series credentials. Jason Varitek was part of the Altamonte Springs (Fla.) team in the 1984 competition.

Revitalized Ortiz

David Ortiz had Monday night off. Last night the Sox’ burly designated hitter showed some speed and hustle on the basepaths.

Ortiz delivered a run-scoring extra-base hit to left-center in the first inning, turning it into a triple with a slide into the third-base bag ahead of a relay throw. And he started Boston’s five-run rally in the fourth by legging out a swinging bunt to the third-base side of the pitcher’s mound.

“I’m sore, bro,” said a smiling Ortiz, who has had problems with his legs all year.

Manager Terry Francona said he didn’t cringe when he saw Ortiz try for third.

“You’ve got to play the game,” said Francona. “He had the play in front of him and he could see he could make it. But (watching him), you put your seat belt on and (feel the) vibrations. He can get (his legs) going when he needs to. I think he was feeling that triple for five innings.”

Saved by a pad

Third baseman Mike Lowell, one of the hottest hitters on the team, escaped injury thanks in part to a pad he wears on the outside of the back of his left batting glove.

Lowell was drilled by a fastball from Tampa Bay pitcher Andy Sonnanstine in the fourth.

“It’s a good thing he had (the pad) because he got hit pretty square,” said Francona. “It didn’t catch all the pad, but the pad really helped.”

Lowell, who entered the game batting .500 (19-for-38) with four homers against the Devil Rays this season, went 1-for-3 last night.

Around the bases

Rhode Island’s Rocco Baldelli went 0-for-3 as the designated hitter for the Rays’ Class-A team in Vero Beach, Fla. He’s 0-for-5 with a walk in two rehab games. … Boston native Carlos Pena, who played briefly for the Red Sox last year, clubbed a two-run homer in the first. It was his 28th homer, a career-high. … J.D. Drew gets criticized for being too passive at the plate, watching too many pitches go by. But last night he swung at the first pitch and put it in play in each of his first two at-bats — a flyout to the wall in center and a single through the shortstop hole. He also swung at the first pitch in his third at-bat, pulling a grounder foul down the first-base line.

skrasner@projo.com