Hu was sent down to Triple-A Durham following the conclusion of Saturday's doubleheader with the Athletics.
Hu filled in admirably in long relief after starter Matt Andriese (groin) lasted just one inning in his return from the disabled list for Game 2 of the doubleheader. The 23-year-old, who was making just his fourth appearance in the big leagues, covered four innings, giving up one run on two hits and a walk while striking out five. Since the Rays only brought Hu aboard Saturday to serve as their 26th man, he wasn't expected to stick with the big club through the weekend, but his solid outing could put him at the top of the list for a promotion the next time Tampa Bay needs relief help.