Oakland's Jharel Cotton (elbow) to undergo Tommy John surgery

Oakland Athletics starter Jharel Cotton will undergo Tommy John surgery, Melissa Lockard of The Athletic reports.

What It Means:

Cotton was expected to be a key part of the Athletics' 2018 rotation, but that will have to wait at least a year. The 26-year-old was initially diagnosed with a strained UCL in his right throwing elbow and a second opinion confirmed the need for surgery. He'll miss the entire 2018 season and could be questionable for the start of the 2019 campaign.

In 2017, Cotton went 9-10 with a 5.68 FIP in 24 starts and 129 innings.