Diamondbacks' Miguel Castro: To IL with shoulder injury

The Diamondbacks placed Castro on the 15-day injured list Tuesday, retroactive to April 21, with right shoulder inflammation.

Castro will undergo an MRI on his right shoulder Wednesday, Theo Mackie of The Arizona Republic reports. The reliever was dealing with discomfort for a bit, but it seems to have gradually gotten worse. He surrendered two runs on four hits across one inning during his last appearance Saturday. The 29-year-old is eligible for activation May 6, a team off day before the start of a series against the Reds. In a corresponding move, Andrew Saalfrank was recalled from Triple-A Reno.