Stymied by Jon Lester early, the Tampa Bay Rays finally got to him in the fifth.
Carlos Pena and Ben Francisco hit back-to-back homers in the three-run fifth as the surging Rays downed the Boston Red Sox, 4-2, in the finale of a brief two-game set.
The red-hot Rays have won seven straight and sit three games behind the Oakland Athletics, who defeated the Texas Rangers on Wednesday, for the AL's second wild card spot.
"I want it to be exactly like last year," Rays manager Joe Maddon said. "It's starting to look a lot like Christmas. We've just been playing so well. The mantra is one game at a time.
Alex Cobb (10-9) struck out five and allowed a run on three hits and three walks over five frames to pick up the win, while Fernando Rodney fired a scoreless ninth and notched his 45th save of the season.
Lester (9-14) held the Rays hitless over the first 4 1/3 innings until Jeff Keppinger lined a single into left field. In all, Lester fanned five and surrendered three runs on four hits and a walk over six frames for Boston, which has dropped six of its last seven contests.
It's the first time that Boston has finished under .500 at Fenway Park since 1997.
"We didn't walk off many and we didn't score enough runs here. We have a lot stored up for next year," Red Sox manager Bobby Valentine said of his team's struggles at home this season.
Following Keppinger's base hit, Pena smashed a two-run shot off the back wall in dead center field and Francisco then launched a solo blast over the Green Monster in left field for a 3-1 Rays advantage.
The Red Sox got a run back in the sixth when James Loney lifted a sacrifice fly to right field, but Tampa Bay regained its two-run cushion in the seventh on a Jose Lobaton one-hop, ground-rule RBI double over the short wall in right-center field.
Wade Davis fanned two during a 1-2-3 seventh, while Joel Peralta spun a scoreless eighth.
Earlier, the Red Sox struck first in the second when Daniel Nava slapped two- out RBI single to right field.
Boston's Dustin Pedroia stole two bases, which gave him 100 for his career ... To conclude the season-long 100th anniversary celebration of Fenway Park, Boston unveiled its 40-man, All-Fenway team as part of a pregame ceremony ... The Red Sox finished 34-47 at Fenway this year, their worst home mark since 1965.