What would you give up for Zack Greinke?

Twitterverse was abuzz this morning with talk of Zack Greinke and the fact that the Texas Rangers were one of the teams to have a scout on hand for Greinke's start this afternoon. That information isn't surprising, as the Rangers fan scouts out to all kinds of places and are big on constantly doing their due diligence in case they need to make a move.

And why wouldn't they be watching Greinke right now? With the pitching staff buying stock in the DL right now, the Rangers must look at every option. They should have plenty of arms returning even prior to the July 31 deadline, but nothing is guaranteed. And Greinke would be an upgrade, too. Coming into today's start, the 28-year-old was 8-2 with a 2.88 ERA. He had 102 strikeouts and 22 walks. The idea of having Greinke, Yu Darvish, Colby Lewis, the club's top postseason pitcher the past two years, and perhaps Matt Harrison, a possible All-Star, ready to go in a playoff rotation is appealing.

A few things to consider:

* Greinke is a free agent at the end of the season, so this would be a three-month rental unless he ends up staying in Texas long-term. But the Rangers can't make the trade expecting that to be the case.

* He won't come cheap. If he's indeed on the market, he's one of the top pitching options out there, and with the additional playoff spots this season, more teams may be interested in making a move to jump into the postseason discussion. That could mean dealing a current big league player and top prospects. I can't think that for a three-month rental, the Rangers entertain thoughts of dealing Mike Olt or Jurickson Profar. Those are pieces you save for a bigger return. But what about someone like Martin Perez? The young prospect could get the start Saturday, depending on what happens with the bullpen, and it would be a chance for scouts to see what he's got. But it's going to take some sort of competitive package and parting with talent to get Greinke.

* What hurts Greinke's value to another team is a rule, now in effect under the new collective bargaining agreement, that doesn't allow the team that trades for Greinke to get the draft pick as compensation.

* The Rangers have made deals with Milwaukee and Doug Melvin before at the deadline. In fact, one of Jon Daniels' early deals was to acquire Carlos Lee and Nelson Cruz for a package of players that included closer Francisco Cordero in July 2006.

* Could Milwaukee trade Greinke sooner rather than later with the idea that the team that acquires him could get additional starts out of him, perhaps increasing his value? Maybe. We saw that Seattle did that with Cliff Lee, when the Rangers got him on July 9, 2010, three weeks before the deadline.

* Texas has liked Greinke for years and was interested when the Kansas City Royals dealt Greinke to the Brewers after the 2010 season.

So what are you willing to give up for Greinke? Would you trade anyone in the rotation right now along with prospects? Are you willing to dangle Olt or Profar for a rental player?