The left-handed reliever started the year with the Red Sox, but after facing 25 batters, posting a 7.71 ERA, and allowing six of his 13 inherited runners to score, he was sent to Pawtucket. Thomas was fine in his 5-1/3 innings of work with the PawSox, striking out five hitters without issuing a walk. But he's 28 years old, and has had that kind of success in the minors before. His limited time in the majors (21-2/3 innings) has not gone nearly as well, though, with a 6.65 ERA, 1.2 K/BB, and of course, the inherited runners allowed to score.
The Yankees have their own left-handed relievers, so expect Thomas to report to Triple-A once again and act as depth, as he likely would have for Boston had he cleared waivers successfully.