Then in his first at-bat in the second inning, Mike Sweeney suffered a back spasm during a check swing while trying to tee off on a pitch from Tampa Bay right-hander Jeff Niemann. The Mariners' medics checked Sweeney out, then ushered him off the field.

Branyan said before Wednesday's game that he thought he'd be able to play Thursday in the afternoon finale against the Rays. If he can't, however, Seattle might have to make some quick adjustments.

For the moment, the Mariners could do what they did Wednesday night, moving second baseman Jose Lopez to first and having utility man Ronny Cedeno take over at second.

However, if the M's go with that alignment and Branyan is unavailable, that would leave Seattle with just a two-man bench, outfielder Wladimir Balentien and catcher Jamie Burke. As it is, Seattle has just a four-man bench at the best of times thanks to the decision to have a seven-man bullpen.

RAYS 9, MARINERS 3: RHP Jeff Niemann, the only rookie on the Tampa Bay roster, pitched like a veteran in leading the Rays to an easy win at Seattle.

Niemann, 26, retired the first 12 batters he faced in order before an error gave the Mariners their first baserunner in the fifth inning. By that time the score was 7-0, and while Seattle rallied a bit on a three-run homer by Jose Lopez, the Mariners were too far out of the game.

Seattle also started a rookie, RHP Chris Jakubauskas, but the results were not at all similar. Jakubauskas gave up four hits and three runs in the first inning, and the Rays scored at least one run from the first through the sixth.

The key blow in the first was a one-out, two-run double by Carlos Pena that got Tampa Bay on the scoreboard.