We're not even two weeks into the 2016 MLB offseason and there's already bad news for the Cleveland Indians.

All-Star outfielder Michael Brantley underwent shoulder surgery on Monday and is expected to miss 5-6 months. His status for Opening Day is in doubt and it's possible he returns to the Indians as late as May.

Brantley underwent arthroscopic surgery, which was performed by Dr. Craig Morgan in Wilmington, DE, to repair a slight tear of the labrum, according to Jordan Bastian of MLB.com.

One year after finishing third in the AL MVP voting, Brantley batted .310/.379/.480 with 68 runs scored, 15 home runs, 84 RBI and 15 stolen bases in 2015 before injuring his right shoulder in late September. He made a diving catch and landed on his right arm against the Minnesota Twins on Sept. 22. He came up to bat the following inning, but exited the game and played only two more times before the season ended.

Manager Terry Francona said Brantley "jammed" his shoulder at the time and later on the team's medical staff believed the 28-year-old could avoid surgery with a rehab program after the regular season ended. However, the pain persisted and Brantley received a second opinion, which ultimately determined he needed the procedure.

Shortly after the Indians announced Brantley underwent surgery, the team's head athletic trainer, James Quinlan, told Paul Hoynes of the Cleveland Plain Dealer that he won't be able to swing a bat for four months, which may indicate he won't be MLB-ready for six months.

Brantley's injury seriously affects the Indians' outfield situation. The unit was already perhaps below average with Abraham Almonte in center and Lonnie Chisenhall in right, so general manager Chris Antonetti may have to explore free agency or the trade market to acquire a capable outfielder.

Some free agents include Denard Span, Dexter Fowler, Gerardo Parra, Yoenis Cespedes, Alex Gordon, Chris Davis, Ben Zobrist, Colby Rasmus, Austin Jackson and others.