An MRI on Rangers starting pitcher Yu Darvish's right triceps showed a sprained UCL in his right elbow, MLB.com's Jesse Sanchez reported.
The team is discussing Tommy John surgery, which would end Darvish's 2015 season.
The Rangers said that the team and Darvish will consult with other orthopedic surgeons over the next few days to determine if the surgery is necessary.
"I will be disappointed if I have to miss this season, but I want to look at all options including getting a second opinion," Darvish said in a release from the team.
General manager Jon Daniels said that the injury was "not the news we wanted" in a meeting with the media, according to Fort Worth Star Telegram reporter Stefan Stevenson. He said that a best case for Darvish would be four months of rest, instead of surgery.