Stephen Kolek

The brother of Marlins 2015 first-round pick Tyler Kolek, Stephen's fastball has never matched Tyler's triple digit radar gun readings, but he'd shown the potential to have three average or better pitches and average control coming into the 2018 season. But his 91-94 mph fastball has backed up this season. There have been outings where he's dipped to pitching in the high 80s. Kolek's slider gives him a chance to survive even with less arm speed. The pitch has less bite at lower velocities and has been more fringe-average than above-average this year. His changeup also has taken a step back this year and he mixes in a get-me-over curveball early in counts. Kolek has shown the ability to be a No. 4 starter at his best, but scouts have only seen that in glimpses this year. His 5-6, 4.58 season isn't making a strong draft case, but there's still something there.