ST. PETERSBURG — The Rays knew closer Troy Percival had to be hurt when he willingly left the mound in the middle of the ninth inning Wednesday.
Percival felt tightness in his left hamstring so severe he fell while delivering a pitch. After trying an awkward-looking warmup pitch, he shook his head and walked off the mound. He had an MRI exam after the game, with the results expected to be announced today. At the least he is expected to miss a few days, and the disabled list is a serious possibility.
"For him to take himself out of the game, it made me worry a little bit," reliever Dan Wheeler said. "He seemed in good spirits, and he doesn't think it's too bad. Hopefully we'll be able to hold the fort down while he's gone."
Even if Percival, who was one out from his 15th save, is out only a few days, the Rays may opt to bolster the bullpen, with Wheeler and/or Al Reyes moving into the closer's role.
RHP Grant Balfour is the leading candidate for a promotion given his extraordinary numbers at Triple-A Durham: 1-0 with eight saves and a 0.38 ERA (one run in 232/3 innings), though he would have to be re-added to the 40-man roster. Among rostered options would be LHP Kurt Birkins, who was effective earlier this season.
If Percival, 38, doesn't go on the DL immediately, the Rays could make room on the active roster by sending down INF Ben Zobrist but holding off on activating INF Willy Aybar, who was to wrap up a rehab assignment at Triple-A Durham on Wednesday. Aybar was 0-for-4 with a walk while playing second base.
Percival felt tightness in the hamstring during his May 20 outing in Oakland, rested a few days and pitched Sunday with no problems. He told manager Joe Maddon before Wednesday's game that he felt good, "maybe the best day he's had in regard to how he's feeling since the last time it occurred."
But after eight pitches, it was obvious something was wrong.
"I knew he was hurting a little bit more, I could see it in his face," Maddon said. "You could see when he delivered the ball that that was not going to work and he just walked off and he knew that he couldn't continue."
HAMILTON'S HOMECOMING: Former Rays prospect Josh Hamilton sounded happy his Tropicana Field debut was behind him, having gone 2-for-12 with five RBIs.
"Good to come, glad to go get back home," Hamilton said. "My wife and kids are coming for the summer. I haven't seen my oldest girl for about a month now, so it's been a while. It was good seeing these guys. I hope they keep doing well."
PRICE CHECK: Top 2007 draft pick LHP David Price made his second start for Class A Vero Beach and was brilliant, going six shutout innings with two hits, nine strikeouts and no walks to outpitch rehabbing Mets star Pedro Martinez.
SERIES STUFF: The Rays have won nine of their past 11 series, six straight at home, losing last to the White Sox April 18-20. The Rangers hadn't lost in nine series going back to April 22-24.
MISCELLANY: The Rays' 17 May wins are their second most in any month of their 11 seasons; they were 20-6 in June 2004. … The Rays drew a season-high-matching nine walks. … Wheeler earned his first save since June 8, 2007, for Houston against the White Sox. … The Rays are alone in first place for a fourth consecutive day, matching their franchise high from earlier this month. … DH Cliff Floyd has reached base in six straight plate appearances. … The Rays are hitting .320 through the first six games of the seasonlong 10-game homestand.
Times staff writer Brant James contributed to this report.