September 1st represents the date that rosters expand from 25 to 40 men. Teams fall into two categories when contemplating who should be called up. Teams going to the postseason use these call-ups to give their players, especially pitchers, a break to keep them fresh for the playoffs.

The second camp are those teams who have all but been eliminated from the playoffs. These teams use the final month of the season to give their rookies playing time. This gives the organization a chance to evaluate players in game situations to decide whether they fit within the team’s plans for next year and beyond.

The 2010 Diamondbacks fit squarely in the second category. The current roster has played so poorly that change is inevitable. The only question is who will be returning next season and who will be gone?

In order for a player to be called up he must be listed on a team’s 49-man roster. With the Diamondbacks, that opens up a whole lot of questions and potentially some drama.

The first domino to drop happened on Tuesday when Arizona released infielder Bobby Crosby. This was somewhat surprising since Crosby has been with the team less than a month coming over in the Chris Snyder trade with the Pittsburgh Pirates.

In a somewhat surprising move, the Diamondbacks recalled Ryan Roberts. It was surprising only because the expectation was for Tony Abreu to return. It is likely that the Diamondbacks want to evaluate Roberts to see if he fits with the team’s plans while Abreu is assumed to have a lock on a roster spot.

It is likely that Abreu will be called up next week. Others likely to be called up include first baseman Brandon Allen and outfielder Cole Gillespie; both of whom have spent time with the Diamondbacks this year.

Some of the more intriguing questions surround the pitching staff. The Diamondbacks signed veteran pitcher Mike Hampton to a minor league deal earlier in the week. He is expected to join the bullpen.

Hampton is not on the 40-man roster. The Diamondbacks have only 38 on the roster so they could use one of the two open spots.

Brandon Webb is still claiming that he will pitch this season. Webb is currently on the 60-day disabled list which does not count against the 40-man roster. If they want to activate him they will need to make room on the roster.

Word has it Leo Rosales is getting close to returning. He too is on the 60-day disabled list meaning a roster spot will need to be opened up if he returns.

Kris Benson, also on the 60-day disabled list, is on a rehabilitation assignment and could return needing another open roster spot.

There has also been a suggestion the Diamondbacks are planning to add a third catcher. There are only two catchers on the roster meaning to add another would require yet another open roster spot.

So the next week could prove interesting not just for the remainder of 2010 but for next season as well.

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