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08/22/12 4:08 PM ET

D-backs shuffle roster for doubleheader vs. Marlins

PHOENIX -- The D-backs made three roster moves prior to Game 1 of Wednesday's doubleheader vs. the Marlins, selecting the contract of Game 1 starter Tyler Skaggs and recalling outfielder A.J. Pollock from Triple-A Reno.

Skaggs took the roster spot of reliever Sam Demel, who was optioned to Reno. Demel had been called up one day earlier and took the loss in Tuesday night's game.

Pollock was designated as the D-backs' "26th man" for Wednesday. Teams are allowed to add a 26th player for doubleheaders scheduled at least 48 hours in advance, with the stipulation that the player must be returned to the Minors following the second game.

Pollock had been up on two other occasions this season when the team placed players on paternity leave. With outfielder Justin Upton's status uncertain early in the morning, the team decided to carry an extra position player rather than an extra pitcher.

Upton's left hamstring feeling better a day after injury

PHOENIX -- Justin Upton was out of the D-backs' lineup for Game 1 of Wednesday's doubleheader, but the outfielder's left hamstring was feeling better one day after he was forced to leave the game in the first inning with tightness in the hamstring.

"I feel a lot better than last night," Upton said. "I got some treatment last night and worked on some things."

Wednesday morning, Upton had an MRI taken as well.

"I had an MRI this morning and everything was good. So as far as I know, I'm available off the bench," Upton said.

D-backs manager Kirk Gibson had already left Upton out of the lineup before the results of the MRI came back and said it was possible he could play Upton in the second game.

That would be just fine with Upton.

"I don't want to be out of this lineup, especially at this time," Upton said. "It looks good, so I'm ready to play."

Saunders not bothered by waiver-wire report

PHOENIX -- A FOXsports.com report said that the D-backs placed left-handed pitcher Joe Saunders on waivers Tuesday.

Players routinely get put on waivers during the month of August. If Saunders is claimed by another team, the D-backs can either work out a trade with that club, allow the claiming team to have him or pull him back off waivers.

Players must go through the waiver process to be traded following the July 31 Trade Deadline.

Recently, the D-backs put shortstop Stephen Drew on waivers and when he was claimed by the A's the two teams worked out a trade.

"Everybody gets put on waivers, it doesn't matter who you are," Saunders said. "I don't pay attention to it. Whatever happens is going to happen, I can't let it bother me."

Steve Gilbert is a reporter for MLB.com. Follow him on Twitter @SteveGilbertMLB. MLB.com reporter Joe Frisaro contributed to this report. This story was not subject to the approval of Major League Baseball or its clubs.