Stanek has touched 94 mph for scouts on occasion but pitches at 89-92 with a power slider in the mid-80s that shows a curveball break. He'll have to stick with the slider, too, most likely, due to a low 3/4 arm slot, which could also make it tough for him to develop a change to keep left-handers honest.
He has a cross-over delivery that some scouts don't like, but Keith Law wrote this spring that Stanek's elbow pronation and long arm path are also concerns, both which worry me more than the step-across delivery.
He's projectable physically at 6-foot-4 and 180 pounds, so there could be more velocity in the fastball -- perhaps enough for him to sit 92-94 and touch 96 when he's fully developed. But the pitch, of the 4-seam variety, has above-average movement at present, though no sink or downward plane, naturally.
His ceiling sits somewhere between a No. 2 and No. 3 starter with the keys being the consistency in his release point, some mechanical adjustments, mainly his arm path, and how he deals with left-handed batters. If he has to pitch out of the bullpen, he could be nasty versus left-hander as a power arm in situational work.
TOOLS -- NOW/FUTURE
Fastball -- 50/60
Slider -- 40/50
Control/Command -- 40/50
Stanek was the third best player available when the Mariners tabbed him at No. 99 overall, and brings good value to that spot in the third round, and he's the second prep arm the club drafted in their first three picks, which means the M's identified the value in the class and went after it, regardless of anything else.
Stanek will need time, just like No. 43 overall selection Taijuan Walker, so dividends may not pay off for four or five years, but the Kansas native, upon signing, would already be the organization's third or fourth best pitching prospect.