Over the first two months of the season, Rubby De La Rosa was close to the best starting pitcher the Diamondbacks had. He had an ERA+ of 104, and was striking out better than a batter per inning. He had his struggles early on, but was dramatically improved after a short stint in the bullpen, posting an ERA of 1.93 over the five starts which followed. However, his last start on May 25 was an abbreviated one, lasting only 4.1 innings, and when Shelby Miller went on the DL on May 27, De La Rosa joined him, with what was officially described as "right elbow inflammation".

An MRI followed, along with a visit to Dr. James Andrews - neither of which are ever a good thing - who cast an eye over the results.