Back in 2014, then Tampa Bay Rays prospect Alex Colome was suspended 50 games for PED use. At the time, Colome was a starter, vying for the Rays fifth spot in the rotation when he tested positive for Boldenone, a steroid used to treat horses. It was a tough blow to Tampa Bay, and likely caused Colome to only have five appearances in the majors that year.
Fast forward to 2017, and Colome has become a key part of the Rays. Instead of being that excellent starter they hoped for, he has become a dominant closer. After making the All Star Game last year, Colome is leading the American League with 34 saves.