Andy Sonnanstine allowed three earned runs over five innings Saturday in a defeat of the Orioles.

Sonnanstine walked four and threw just 62 of his 99 pitches for strikes. But he pitched well enough, and should remain in the Rays' rotation until either Wade Davis or Jeff Niemann returns from the disabled list. If he starts next week, it will be against the A's in Oakland.

Rays activated RHP Andy Sonnanstine from the 15-day disabled list.

Sonnanstine, sidelined with a hamstring strain since July 23, will return to the Rays' starting rotation on Sunday for a fill-in outing against the Blue Jays. He will head back to his long relief role in the bullpen once Jeff Niemann is no longer feeling soreness in his throwing shoulder.

Andy Sonnanstine will make a spot start for the Rays on Sunday.

He will fill in for Jeff Niemann, who was scratched from the outing due to shoulder soreness. Sonnanstine had a 4.22 ERA and a 1.18 WHIP over 49 innings before his disabling and can be avoided in fantasy leagues.

Manager Joe Maddon said Andy Sonnanstine (hamstring) is likely to return to the roster on Sunday.

Sonnanstine is already with the club, but recently recalled Dale Thayer will stay on the roster for one more day. The right-hander has been good as a long man out of the bullpen this season, posting a 4.22 ERA, 1.18 WHIP and 35/11 K/BB ratio over 49 innings.

Rays placed RHP Andy Sonnanstine on the 15-day disabled list, retroactive to July 23, with a left hamstring strain.

Sonnanstine hasn't pitched since July 18 due to the hamstring injury. His disabling clears the way for the promotion of top pitching prospect Jeremy Hellickson, who is making a spot start on Monday vs. the Twins.