DETROIT (AP) — Detroit Tigers right-hander Casey Mize, the top pick in the 2018 June draft, will undergo Tommy John surgery.

Tigers manager A.J. Hinch made the announcement. The 25-year-old Mize has been on the injured list with a right elbow sprain since April 15 after making two starts this season. The date of surgery has not been determined.

Mize got two outs for Triple-A Toledo on May 12, then had his rehab program slowed down. Mize has a 7-13 record with a 4.29 ERA in 39 big league appearances, all of them starts.