Snell complained of a sore elbow after lasting four innings during an 8-5 loss to Toronto on Sunday. Tests on Monday showed no ligament damage, and he was expected to miss only one start.
Snell, the Pirates' opening-day starter, has won once in 13 starts since April 12.
With Snell and left-hander Phil Dumatrait (left shoulder bursitis) on the disabled list, right-handers Jimmy Barthmaier and John Van Benschoten will be brought up from Triple-A Indianapolis to start against Tampa Bay.
Barthmaier will pitch Friday and Van Benschoten, 0-2 with the Pirates earlier this season, will start Saturday.
