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07/14/12 1:15 PM ET

Corbin optioned to Triple-A Reno

CHICAGO -- To make room on the roster for Saturday's starter Joe Saunders, the D-backs optioned left-hander Patrick Corbin to Triple-A Reno.

Saunders had been on the disabled list since June 23 with tightness in his left shoulder.

A starter throughout his time in the Minors and during his first stint this year with the D-backs, Corbin had been pitching out of the bullpen. With a stretch of 20 games in 20 days, and after watching his starters not pitch deep into games, manager Kirk Gibson needs relievers that can pitch on consecutive days.

Given that Corbin has never done that in his career, the team did not want to have him do that now.

"I guess, ultimately, we weren't very comfortable asking him to do that yet," Gibson said.

In addition, by returning to Reno, Corbin will be able to start again and continue to build up his innings.

Corbin said he understood the move and was thankful to have gotten another taste of the big leagues.

"He's done a phenomenal job," Gibson said. "We really like the kid a lot. He's got a great future."

Towers addresses trade rumors with Upton

CHICAGO -- D-backs general manager Kevin Towers met with Justin Upton on Friday to discuss the recent trade rumors involving the right fielder.

"We had a good conversation [on Friday], and I think he gets it," Towers said.

Towers created a stir when he confirmed reports that he would be willing to listen to trade offers for the 24-year-old Upton. Towers explained it by saying that it has always been his policy to listen to offers on any of his players, and he explained as much to Upton.

"I said, 'Hey, this is no different than the way I approached it even before you got to know me in 2010. I listen on everybody,'" Towers said. "We're in the information gathering business. I said, 'If something gets close, you'll be a part of the process. I'm not going to shock you with something. If something is coming down and I think it's close, there will be a heads up.' I said, 'At this point in time, a lot of people are kicking tires. Your name is out there a lot, most of it is untrue.'"

Towers also addressed his desire that the rumors not become a distraction for Upton, who is a key part of a lineup on a team battling for a playoff spot. He also reassured Upton that nothing is imminent.

"[I told him], 'I don't want that to be a distraction for you,'" Towers said. "'You're a big part of this club and we need you right now. If anything, you should look at it in a good way -- that people like you, not just the Diamondbacks, but you're perceived very well throughout baseball.'"

Worth noting

• Towers continues to work the phones in advance of the July 31 non-waiver Trade Deadline.

"A lot of clubs are probably like us, kind of still trying to wait until the very end to figure out where you're at," Towers said. "We're still within five games, but a lot can happen in a couple of weeks. You could have a big winning streak, you could have a big losing streak and it could change things."

• D-backs right-hander Ian Kennedy, a 21-game winner in 2011, has struggled to find consistency this year.

"Doesn't have quite the location he had last year," Towers said. "I think he was down in the zone a lot more last year, driving the ball down in the zone. His command is just off, he's elevating too many balls and getting too much of the plate."

Kennedy's velocity has been down, but Towers did not sound overly concerned about it.

"It could be the innings of last year," Towers said. "You're just hoping it's a little blip and he's going through an extended kind of dead-arm period, where he just doesn't have the [velocity]. He's a smart pitcher, and there's no reason to believe he's not going to get it back."

• D-backs left fielder Jason Kubel was out of the starting lineup on Saturday, one day after feeling discomfort in his right hamstring while slipping on the wet field.

While the injury is not believed to be serious, it also hadn't improved a lot since Friday and the D-backs plan to be extremely cautious with him.

Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @dbackswriter. This story was not subject to the approval of Major League Baseball or its clubs.