Since September 1st, the Diamondbacks have had two waves of call-ups, or bringing members of their minor league clubs to the major league level. The first wave was the largest, bringing on four players (Tony Abreu, Brandon Allen, Carlos Rosa, and Leo Rosales). The second wave saw Arizona add two players (Zach Kroenke and Mike Hampton).

Indications were these would be the only additions to the roster. It was therefore surprising to arrive at Chase Field before last night’s game and see outfielder Cole Gillespie in uniform and warming up.

Gillespie has had two stints with the Diamondbacks this season with some levels of success. He has played well defensively while struggling during his last appearance with the Diamondbacks.

I had expected to see Gillespie on September 1st, but he seemed to be the forgotten player being left in Reno while others were called up to Phoenix. With Allen now getting time in the outfield as well as first base, you had to wonder whether Gillespie was still in the mix for a roster spot next season.

He may not have received an invitation back to the big leagues were it not for the injury Justin Upton received tweaking his shoulder during an at bat. Upton has been out of the line-up for seven games, and according to reports, his shoulder is not responding to treatment.

Rather than playing down an outfielder, the Diamondbacks recalled Gillespie to fill in until the team knows more about Upton’s injury.

After an MRI, team doctors do not believe the shoulder is structurally different than it was when Upton arrived at the major leagues in 2006. That is not to say there is no damage, just no more damage in the past four years.

Upton’s brother BJ had a similar shoulder issue and went under surgery to repair damage to his labrum. Team officials are not suggestion Justin have something similar, but if his shoulder does not get any better over the next week, there may be further discussions going into the offseason.

In the meantime, Gillespie received a return trip to Chase Field. It will be up to him to make the most of this opportunity and show team officials he belongs on the roster going into Spring Training 2011.

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