Triple-A Pawtucket outfielder Che-Hsuan Lin was recalled in Ellsbury's place, but the plan is for Lin to be only a temporary fix. Cody Ross started in center Saturday afternoon.
No timetable was set for Ellsbury's return, but subluxations -- when the upper arm comes partially out of the shoulder socket beyond what is normal -- can typically take six to eight weeks to return, or more. The team should know more after further evaluations.
"He'll continue to be examined and we will try to get him back as soon as possible with the best possible care known to man," said manager Bobby Valentine, who met with Ellsbury at Fenway Park on Saturday morning. "I haven't heard the word surgery mentioned, but as I say, whatever the best possible care is, that's what he'll get.
"I texted him last night, because I thought that was the best thing and told him if he needed me, I'd be there. And we met this morning. He obviously didn't sleep much and he's obviously disappointed."
Ellsbury was with the Sox for Saturday's 13-5 win over the Rays and received his 2011 American League Gold Glove and Silver Slugger Awards in a pregame ceremony, but he left without speaking to reporters. Valentine said after the game he had no further update.
Ellsbury was taken to Massachusetts General Hospital for observation Friday, and an MRI revealed the subluxation.
Coming off a 2011 campaign that saw him finish second in American League Most Valuable Player Award voting, Ellsbury was off to a 7-for-26 start when he suffered the injury in the fourth inning of a 12-2 win over Tampa Bay at Fenway. Trying to break up a double play with a feet-first slide, he collided with Rays shortstop Reid Brignac at second.
Ellsbury broke from first on the 3-2 pitch to Dustin Pedroia, and Brignac knew Ellsbury was hurt.
"Yeah, I could hear him and it sounded like a very painful thing," Brignac said. "I kind of landed on him, rolled off. He was yelling and screaming a little bit. I just went over to check on him, because obviously that's not how I play the game. It was just an unfortunate thing."
After Friday's game, the Red Sox were all concerned for one of their core players, who posted a .321/.375/.552 line with 32 home runs and 105 RBIs in 2011.
In 2010, Ellsbury played in just 18 games after fracturing his ribs. Last season, he quieted any concerns about his durability by playing in 158 games.
Valentine said he suffered a subluxation in his playing days, and that he probably tried to return from the injury too soon.
"Some guy threw me down at home plate one time and it happened to me," Valentine said. "It's painful."