Here's a look at what Tuesday's trade means going forward:
Who plays shortstop?
Gregorius will get the opportunity to win the starting job during Spring Training, but with Cliff Pennington, Willie Bloomquist and John McDonald also on the roster, they can afford to be patient with Gregorius.
Towers said that spending some time in Triple-A would not be a terrible thing for Gregorius, who only has about a season and a half of experience at the Double-A level and above.
Who's the odd man out at short?
First of all, everyone has to remain healthy. Bloomquist is coming off some back issues, so look for the D-backs to hang on to all their infielders heading into Spring Training. Towers has said that in the past, he's found that teams always seem to be looking for middle-infield help in March, so he figures he'll have some trade options at that point.
It seems at this point -- and again, a lot can happen between now and then -- that McDonald would be the odd man out if everyone is healthy.
What does Tuesday's trade mean for Justin Upton's future?
Now that the D-backs have acquired a player they feel can be their shortstop going forward, it means that Upton is all but certain to be with the D-backs come Opening Day.
Towers did leave some wiggle room when the GM said that he remains open to "listening" to offers for any of his players. However, the two main needs the D-backs had this offseason -- finding an upper-rotation starter and a shortstop -- have been filled without having to part with Upton, so it seems extremely unlikely they would deal him now.
"I have not heard of a deal yet that we've talked about -- and believe me, we've talked about a lot of them -- that makes us a better ballclub, and I would say at this point in time, I don't think [an Upton trade] is going to happen," Towers said.
Are the D-backs done dealing?
The D-backs are done with the moves they felt they had to make this winter, but they might not be done just yet.
They still would like to thin out their outfield ranks, and it appears they think Gerardo Parra is a better fit going forward than Jason Kubel, so they will likely continue to talk with teams about Kubel.
It would not be a surprise to see the D-backs sign closer J.J. Putz to an extension. Towers publicly expressed interest in doing that when he announced that the team was picking up Putz's 2012 option, and Putz has made no secret of the fact that he wants to finish his career in Arizona.
First baseman Paul Goldschmidt and second baseman Aaron Hill are also extension candidates. Hill might be a tougher sign of the two given that he is coming off an outstanding season and has a lot of leverage. However, Hill doesn't appear to be someone who is overly motivated by money, and he and his family are comfortable in Arizona and have, in fact, made their year-round home here.