Boston's David Ortiz, left, greets teammate Mike Lowell after Lowell's home run during the first inning against Tampa Bay Tuesday. Ortiz hit a three-run home run earlier in the inning as the Red Sox crushed the Rays 13-5.

ST. PETERSBURG, Fla. — The Boston Red Sox flexed their muscles, nudging closer to first place in the AL East.

The defending World Series champions homered a season-high six times, overwhelming All-Star Scott Kazmir and division-leading Tampa Bay 13-5 Monday night to pull within percentage points (.002) of ending the Rays' two-month stay atop the standings.

"These guys have been playing well all year long, and we haven't been playing well here at all," Boston reliever Mike Timlin said the Red Sox won for the first time in seven games at Tropicana Field this season.

David Ortiz, Mike Lowell, Jason Bay, Jason Varitek, Kevin Youkilis and Jacoby Ellsbury homered for the Red Sox, who jumped on Kazmir for four runs in the first inning and never let up.

"That was just a good old-fashioned whippin' tonight," Rays manager Joe Maddon said, adding that he doesn't expect it to have an adverse effect on his young team the next two games of the series.

"Believe it or not, this is an easier loss to accept. When you lose 2-1 or 3-2 on one play ... those are the ones you go home and kind of beat yourself up after."

The Rays (88-60) went 21-7 in August and were a season-high 5Z\x games up on Boston heading into September. They're 4-9 this month, with six of the losses coming against the Red Sox and Yankees, who took two of three from Tampa Bay over the weekend.

The Red Sox (89-61), on the other hand, have won three straight and 10 of 14 in September to get as close to the lead as they've been since mid-July, when they erased a five-game deficit in a week to pull ahead by a half game at the All-Star break.

While both teams are in excellent position to make the playoffs, neither wants to settle for the wild card.

"We want to finish first," Red Sox manager Terry Francona said. "That's what you set out to do."

Ortiz, who finished with four RBI, hit a three-run homer in the first inning after Kazmir (11-7) threw nine straight balls to begin the game. Two batters later, Lowell hit a solo shot for a 4-0 lead.

The Red Sox added seven more runs in the fourth, helping Daisuke Matsuzaka (17-2) become the first Japanese-born pitcher to win 17 games in a season. Hideo Nomo won 16 games for the Los Angeles Dodgers three times (1996, 2002, 2003).

Bay and Varitek homered in the fourth off Kazmir, who allowed nine runs and six hits in three-plus innings — his shortest outing of the season. The four homers he yielded were a career high.