Nick Johnson's two-run blast in the bottom of the seventh inning was the difference, as Baltimore topped Tampa Bay, 4-3, in the opener of a three-game set from Camden Yards.
"The main thing is, we got a win," said Johnson. "And guys are playing the right way and we have to continue that. It's a long season."
Adam Jones and Nick Markakis each hit solo homers for the Orioles, who were coming off losing three of four at home against Texas.
Darren O'Day (3-0) turned in a scoreless top of the seventh to earn the win, and Jim Johnson notched his 10th save with a perfect ninth.
Elliot Johnson and Carlos Pena drove in the runs for the Rays, who skidded to their fifth loss in six games.
Joel Peralta (0-2) took the loss and the blown save after serving up the deciding home run.
Tampa starter Jeremy Hellickson retired the first two batters in the seventh, but allowed a single to Chris Davis, and his night was complete. Enter Peralta, who promptly surrendered Johnson's winner, his first longball of the season, to put the O's on top.
"That's the part that hurts the most. Your starter pitchers a good game and you ruin it," said Peralta.
Pedro Strop and Johnson then combined to set down the last six Rays of the contest.
Tampa got on the board in the second when Sean Rodriguez grounded into a run- scoring double play, but Jones' leadoff homer in the bottom half squared the score.
The Rays moved ahead 3-1 in the fourth on a Johnson single and Pena hit-by- pitch, both with the bases loaded.
Markakis reached the seats in right-center in the home sixth to make it a one- run contest.
Baltimore has won its last three home tilts against Tampa Bay...Hellickson ended up allowing five hits and three runs over 6 2/3 innings, while his counterpart Dana Eveland -- recalled from Triple-A Norfolk prior to the contest -- lasted six innings and gave up three runs on five hits with six walks and two strikeouts...In other Orioles roster moves, the club placed pitcher Matt Lindstrom on the 15-day disabled list with a right middle finger injury and also designated infielder Zelous Wheeler for assignment...Also for Baltimore, pitcher Tsuyoshi Wada underwent elbow ligament replacement surgery on his pitching shoulder.