No timetable for recovery was mentioned, but it could impact at least the start of the 2016 season for Alvarez.
"He's in surgery right now for the shoulder," Miami manager Dan Jennings announced on Tuesday afternoon. "I think he's a definite out-for-the-season candidate now."
As for being ready for Spring Training, Jennings noted: "To be determined. I think it's depending upon the actual severity of the tear. And the timetable, we'll know more when the procedure is complete."
Alvarez never was able to get his season going. He made just four starts, and is on his second disabled-list stint.
Even though he took the mound on Opening Day, Alvarez hasn't resembled the starter who was an All-Star in 2014. His season ends at 0-4 with a 6.45 ERA.
The Marlins placed him on the DL on April 13. He returned on May 17, but after two more starts, he went back on the DL.
There was hope Alvarez would return in August. The right-hander was sent on a rehab assignment with Class A Advanced Jupiter on July 15, but he was shut down a week later after experiencing discomfort in a between-starts throwing session.
"It's a little frustrating," Jennings said. "You don't want to see anyone injured, but certainly you don't want to see your guys get shut down for an extended period of time."