ST. PETERSBURG, Fla. – Wade Davis went to a new pitch and finally had success against the Boston Red Sox.

Davis threw a six-hitter, John Jaso hit a three-run homer and the Tampa Bay Rays moved within 5½ games of AL wild-card leading Boston with a 7-2 victory over the Red Sox on Friday night.

“It’s actually the first time I’ve really started throwing a cutter,” Davis said. “I’ve always thrown a slider and we just flattened it out a little bit to stay in the strike zone more. It ended up being pretty effective.”

Davis (10-8) struck out eight in his second career complete game. The right-hander, who had his other complete game on Sept. 17, 2009, had gone 0-2 with an 11.12 ERA in three previous starts against Boston. Tampa Bay pitchers have 15 complete games this season.

“He had a pretty good cutter going,” Red Sox Manager Terry Francona said. “Threw it outside, inside and just ate us up.”

Jaso put the Rays ahead 3-0 with a three-run homer off John Lackey (12-12) in the second. He entered 8 for 37 (.216) in 14 games since returning from a strained right oblique last month.

Boston has lost five of six.

After two more games in Florida this weekend, the Red Sox will host Tampa Bay in a four-games series that starts Thursday at Fenway Park.

“We do believe,” Rays Manager Joe Maddon said. “It’s all about one at a time. But obviously we have to make a big dent with these seven games.”

Rays designated hitter Johnny Damon was back in the lineup after missing the previous three games because of a sore right leg. He had an infield single during the third that moved him past Doc Cramer into 62nd place on the all-time hits with 2,706.

Damon and Matt Joyce had RBI singles in the third to made it 5-0. Jaso later in the inning hit a two-out shot with the bases loaded off Lackey’s left leg, but the pitcher recovered to pick up the ball and throw the Rays’ catcher out at first.

Lackey left with a bruised calf and was replaced by Scott Atchison to start the fourth. Lackey, loser of three consecutive starts, gave up five runs, five hits and three walks on 69 pitches.

The Red Sox have not ruled out Lackey making his next scheduled start.

Jacoby Ellsbury extended his hitting streak to 14 games with an RBI infield single during a two-run sixth that got Boston within 5-2.

The other run scored on Marco Scutaro’s sacrifice fly.