"We think we still have a chance to win right now and I haven't seen anything out there that makes us a better ballclub in 2012 that's better than Justin Upton."
Upton finished fourth in the National League Most Valuable Player voting last year and appeared to be on the brink of reaching the stardom expected of him since Arizona made him the No. 1 overall pick in the 2005 First-Year Player Draft.
This year has been a bit of a struggle for Upton, and he's been booed by the crowd at Chase Field at times. Entering play Tuesday, Upton was hitting .276 with eight homers and 41 RBIs.
Towers, though, said his philosophy throughout his career has been to listen to offers on any of his players, and that the D-backs were not shopping Upton.
"I think what people need to know specifically in Justin's case is I didn't just throw his name out there and say he's available," Towers said. "I think people saw he was kind of having a down year the first two or three months based on what he did last year. I did talk about him [with other clubs] in 2010 and our club was struggling, so why not place a call?
"My response has always been the same and it always will be: I'll listen on anybody. That's not to say he'll be easily moved, but I'm not going to change. I've been consistent that way and always will."
Whether something happens with Upton during the offseason remains to be seen, but he is under contract for the next three seasons.
"It's perceived ... by some media outlets out there that we just wanted to get rid of the guy," Towers said. "That is not the case. It's never been the case. He's a great player and a good Diamondback player and somebody that we respect a lot. It would take an awful lot, kind of a win-type deal for us to consider moving him. Didn't happen in 2010 and so far in 2012, it hasn't happened either."
While it always seemed a long shot that Upton would be dealt, a trade involving Drew was perceived to be more likely.
Drew can be a free agent at the end of the season, as there is a mutual contract option for $10 million for 2013 that the D-backs almost certainly will not exercise.
Then there is the matter of D-backs managing general partner criticizing Drew for the amount of time it took him to return from an ankle injury he suffered last July.
Drew returned to action June 27 and has hit .217 in 60 at-bats.
"I don't think there's a deal out there right now involving Stephen that's going to make us a better club this year and we're still in win mode," Towers said. "If we fall out of this thing middle of August, late August, we still have trade waivers and if we don't know if we're going to be able to bring Stephen back then maybe it's different.
"People kick tires, they ask about him, I don't blame them. But I haven't seen or heard anything right now that by trading Stephen Drew is going to make us a better club."
The departure of third baseman Ryan Roberts on Tuesday decreased the odds of Drew getting moved, as it has thinned out the infield ranks a bit.