SEATTLE -- First baseman Mike Sweeney had to leave the Mariners game against the Rays midway through his first at-bat on a chilly Wednesday night at Safeco Field because of muscle spasms in his upper back.

He will be re-evaluated on Thursday.

Sweeney, batting .313 going into the second game of the series, swung and missed a 1-2 pitch from Rays right-hander Jeff Niemann in the second inning and grimaced in pain.

He stepped away from the plate and tried to take a couple of practice swings, but bent over again, prompting a visit from manager Don Wakamatsu and head athletic trainer Rick Griffin.

It became apparent that Sweeney would not be able to continue and was replaced by Ronny Cedeno.

"Somewhere in the mid-back region, I got a huge muscle spasm and it buckled me," Sweeney said after the Mariners' 9-3 loss to the Rays. "I tried to continue the at-bat, but couldn't do it."

It is the second time in less than a week that a Seattle first baseman has been felled by a back ailment. Russell Branyan has missed the past five games with back spasms.

Sweeney said he expected to be able to play again in a day or two.

He was walking around the clubhouse after the game without any noticeable discomfort.

"Traditionally, when the muscle spasm goes down I'll be fine," Sweeney said. "Maybe in a day or two at the most maybe I'll be ready to go."

Sweeney said he "felt something" on a check-swing during the at-bat. "When I raised my bat up, there was a huge spasm. I told the trainer and Wak I wanted to finish the at-bat and they said 'See how you feel'. I tried to take a swing and it buckled me again.

"But I'll be ready to go in a day or two."