Adam Loewen hit the go-ahead two-run single in the eighth inning as the Toronto Blue Jays rallied to beat Boston 5-4 at Fenway Park on Wednesday.

The Red Sox maintained their four-game lead in the American League wild card standings over Tampa Bay, which lost 6-2 at Baltimore on Wednesday.

Struggling Red Sox reliever Daniel Bard walked the first two batters of the eighth inning and Loewen, a converted pitcher, made him pay by hitting a single to second base that brought home Kelly Johnson and Mark Teahen.

Bard (2-8) surrendered all three runs in the eighth and has been torched for eight runs over his last 2 1/3 innings. He also had a throwing error in the fateful inning.

Boston looked to be headed to its second straight win after cutting down a runner at the plate in the sixth inning and then immediately adding to its advantage in the bottom of the frame on an Adrian Gonzalez solo homer. Gonzalez left the game after the homer with a tightness to his left calf.

Ricky Romero (15-10) won for the eighth time in his last nine decisions, allowing four runs on eight hits over eight innings. Frank Francisco pitched a perfect ninth for the save.

Johnson and Edwin Encarnacion had first-inning RBI singles off Boston starter John Lackey.