He did not get a hit in his first two at-bats, but when he stepped to the plate to lead off the sixth, Pearce hit the first pitch from right-hander Edward Mujica and deposited the ball over the wall in left field for his first home run of the spring.
"I don't like being sidelined, just glad it's behind me," said Pearce, who acknowledged that he was encouraged by Thursday.
The Rays signed Pearce as a free agent on Jan. 28. He will make a base salary of $4.75 million with $1.5 million available in incentive bonuses.
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Pearce, 32, hit .218 with 15 home runs and 40 RBIs for the Orioles in 2015, but he is one year removed from a career year in 2014, when he hit .293 with 21 home runs and 49 RBIs. He will likely see time in left field, at first base, third base, second base and designated hitter.
Pearce said his injury felt "like a little strain" initially.
"I could do everything on it except just explode," Pearce said. "For baseball, being at first base, where you have to react and explode. And when you're hitting, you have to explode on the baseball and when you're running. It was hampering me a little bit. So I was fortunate to get out in front of it, and now it's fine."
He will play first base Friday when the Rays host the Red Sox.
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Pearce said the time away has felt more like a "pause" than a setback.
"I've only missed a week," Pearce said. "But this is a very important part of preparation for the season. You need the at-bats, find ways to slow the game down, so I would say more of a pause."
Pearce will likely get the opportunity to make up some of his missed at-bats on Sunday morning during a "camp day" at the Charlotte Sports Complex.