Valera will undergo an MRI on his right elbow after exiting his most recent start for High-A Greenville last Thursday, Tim Healey of The Boston Globe reports.
Valera missed three months last season with right elbow inflammation. The 19-year-old was placed on Greenville's 7-day injured list Friday, and while the Red Sox seem optimistic that he's not dealing with structural damage to his elbow, more will be known once the imaging results are in. Valera boasts a 1.93 ERA and 17:4 K:BB over 9.1 frames so far this season with Greenville.