Kolek is in the final stages of rehab from his Tommy John surgery, and is hoping to get back on the mound in May, The Miami Herald reports.
Still only 21, the second overall pick in the 2014 draft has had a brutal start to his pro career, showing poor control and command in the low minors for two seasons before blowing out his elbow last spring. Kolek still rates as one of the top prospects in a talent-starved Marlins system, but in most dynasty leagues there's little reason to use a roster spot on him until he shows any kind of progress.