Asked if he thought he could rehab in time to return in 2014, Profar said: "I don't know. I don't think so."
The 21-year-old was slated to start at second base for the Rangers after the club dealt All-Star infielder Ian Kinsler to Detroit for first baseman Prince Fielder. But Profar experienced shoulder issues in spring training and was placed on the disabled list before the season began.
He rehabbed his shoulder but had a setback and was shut down a few weeks ago. Profar said Tuesday that he's not doing any baseball activities right now.
"You want to play, but at the same time you don't want to play hurt and make it worse," Profar said.
Profar, the No. 1 prospect in baseball in 2013 according to ESPN.com's Keith Law, said he does not need surgery. Rest and a slow rehab process are required to fully heal the muscle.
His absence means opportunity for prospects Rougned Odor and Luis Sardinas, who were called up from Double-A Frisco recently. Odor, 20, is getting the bulk of the playing time at second base and has hits in seven of his last nine games. He set a career high with five RBIs and four hits, two of them triples, last month in Detroit. He was the first player under 21 years of age with four hits and five RBIs since Al Kaline in 1955.