First baseman Justin Smoak launched a three-run home run in the bottom of the eighth inning as the Mariners' magical May concluded with a 3-2 come-from-behind victory over the Orioles on Tuesday at Safeco Field.

After being held to three hits by Baltimore's Jeremy Guthrie through seven innings, the Mariners ignited after a fielding error by Guthrie opened the door for the dramatics.

Guthrie couldn't handle a throw at first that allowed Ichiro Suzuki to reach base with two outs. Brendan Ryan then singled to right before Smoak unloaded with his eighth home run of the season.

Playing in front of the smallest crowd in Safeco Field history, 11,692, the Mariners (28-26) ended the month of May with a 15-11 record, their first winning month since June of last year, and they now sit just a half-game back of first-place Texas in the American League West.

Seattle has taken advantage of outstanding pitching to climb back into contention, its starters posting a 2.93 ERA in May that just missed the lowest mark for a calendar month in club history -- 2.81 in September 2003.

Erik Bedard pitched well again, giving up two runs over 6 1/3 innings with six hits, one walk and seven strikeouts against his former squad. Chris Ray picked up the win in relief, also against his former team, as he pitched 1 2/3 innings of one-hit ball before Brandon League closed with his 15th save.

Bedard (3-5, 3.41 ERA) has been outstanding over his past six outings with a 2-0 record and 1.37 ERA, allowing just 27 hits and eight walks with 35 strikeouts in 39 1/3 innings.

He saw his scoreless streak snapped at 20 innings when the Orioles pushed across a run on a double-play groundout by Nick Markakis in the sixth, after a leadoff walk to Robert Andino and a single by Adam Jones.

Catcher Matt Wieters added another run with a blast to right field leading off the seventh, the first home run Bedard has allowed in his past six starts.