"Great, great," said Upton when asked how his shoulder felt. "... It's the best it's ever felt initially, right after [the injury happened], and same result today. So I'm probably going to head down to the cage take a few swings and see what it feels like."
Upton, who had doubled and struck out in his previous two trips to the plate Thursday, swung at a 1-1 pitch from Orioles left-hander Brian Burres in the fifth inning, then crumpled to the ground holding his left shoulder.
Upton suffered the same type of injury on Aug. 17, 2006, and missed three games.
"[It] just feels kind of funny -- it hurts initially, then it feels like it's not really there," said Upton when asked to describe what the injury felt like. "... [It happens] when I kind of get out front [with my swing]. ... [I] can't really tell you exactly what does it.
"Normally, [this type of injury] happens once a year and it's normally later in the year when you're getting tired."
Upton thought it was strange that the injury happened this early in the season -- particularly since he did not experience such an injury last season.
"Hopefully, this is the last time," Upton said.
Upton, who is hitting .294 with three home runs and 21 RBIs, was available for pinch-hitting and pinch-running on Friday night. He will likely be in the lineup on Saturday.
With right-hander Gary Glover going on the 15-day disabled list with right shoulder tendinitis, the Rays recalled outfielder Justin Ruggiano from Triple-A Durham to give the team some outfield insurance for two days until they have to activate Scott Kazmir prior to his start against the Red Sox on Sunday.
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.