The Seattle Mariners are brimming with up-and-coming prospects and that’s on full display within SI Fantasy expert Shawn Childs’s list of five sleepers from the Emerald City.

Sleeper: SP Justus Sheffield

After looking close to the majors after pitching well at AA and AAA in 2018 (2.48 ERA and 123 Ks over 116 innings), Sheffield ended being a bust for any fantasy owner thinking he would help in 2019.

His season began with four reasonable starts at AAA (3.93), but he walked 14 batters over 18.1 innings. The Seattle Mariners gave him one start in late April (two runs, seven baserunners, and four walks over three innings), before shipping him back to AAA.

He pitched so poorly in nine starts (8.35 ERA and 1.991 WHIP), the Mariners had to drop him in class to AA. Sheffield regained his form over ten starts (1.49 ERA, 0.9949 WHIP, and .218 BAA over 66.1