Nelson was sidelined for the past three months with a right elbow strain, but he's finally been cleared to return after yielding two runs with a 4:0 K:BB over 2.2 innings in two rehab outings with Triple-A Reno. The 28-year-old will be utilized in a relief role down the stretch for the Diamondbacks.

Nelson worked 34 pitches in his third and potentially final rehab outing. This was the first of his three that he was used for more than one inning. Nelson has allowed two runs on four hits, struck out six and hit a batter over 3.2 innings while on assignment.