Williamson has had a tough time in his first three Double-A starts, giving up 11 runs on 18 hits with a 13:6 K:BB through 14 innings.
That stands in stark contrast to his performance with High-A Everett, where Williamson pitched to a 3.19 ERA and 1.00 WHIP with a mind-bending 17.1 K/9. The big lefty has certainly been hit hard since being promoted to Double-A, but it's a small sample, and it wouldn't be surprising to see him get right soon. There's a fairly high level of variance with Williamson, as he could end up as a mid-rotation starter or a bullpen guy. As is often the case for pitching prospects, command refinement and further development of his offspeed stuff are the keys to his future.