The Chicago Cubs disengaged recently from trade talks that would have brought Justin Upton to Chicago from the Arizona Diamondbacks, according to ESPN Chicago. Arizona reportedly wanted Cubs shortstop Starlin Castro in return for Upton.

That’s hilarious. If true, it unequivocally explains the Cubs’ abandonment of any pursuit of Upton. Starlin Castro is younger, plays a more important position, is on a much more team-friendly contract, will be locked in longer and is healthier than Upton. Upton is the better overall player, for the time being, but under absolutely no circumstances will or would the Cubs surrender Castro for him.

Diamondbacks GM Kevin Towers knows this. He’s not an idiot. At this moment, the difference between Castro and Upton is such that the Diamondbacks would have to add something to Upton in order to find common ground with the Cubs, and even then, the Cubs would probably want a window in which to work out an extension for Upton beyond 2015 before finalizing the agreement.

No, Towers asked for Castro for the same reason for which he all but traded Upton to Seattle (only to have Upton bang the deal, which, again, Towers knew how that would end), and the same reason for which he has thus far stood firm in asking the Texas Rangers for the world. Towers is setting a market rate, a reserve price in the auction for a promising player on whom he has soured.

He won’t get Castro. But despite the Cubs being on Upton’s no-trade list, there’s a nonzero chance Towers could make that deal actually happen in a different form. By setting the bar so high, he creates an anchoring effect. If he had gone to the Cubs and asked right away for Jeff Samardzija, Arodys Vizcaino and Javier Baez in return for Upton, he’d have gotten nowhere. By starting so radically high, though, Towers has made a package like that one sound more palatable. That’s not to say Theo Epstein and Jed Hoyer, who make the Cubs’ decisions, will fall for the gambit, but Towers has put it out there. You never know.

If I were the Cubs, by the way, under certain conditions, I would probably do the latter deal mentioned above. The key conditions, all involving knowledge I am not positioned to have, are these:

1. I would need to feel confident in Matt Garza’s health, and be ready to commit to him for multiple seasons beyond 2013. In that case, Samardzija would be expendable on some level.

2. I would need to believe Vizcaino is a likely reliever, or that he just doesn’t have the health profile to be an especially valuable long-term asset.

3. I would need to believe firmly in one of Arismendy Alcantara, Junior Lake, Christian Villanueva, Logan Watkins and Ronald Torreyes, making Baez a tolerable loss, or think that Baez’s lack of offensive refinement will stop him from reaching his potential.

4. I would need to put Upton through a thorough health exam, to make sure his injury problems will not prevent him from playing to his potential through the end of his time in Chicago.

If those things were all true, of course, the Diamondbacks would probably know some of them, and the Cubs would need to kick in more. Maybe then the deal falls apart. If a deal does materialize between the two sides, though, it will look like the one modeled, not like the Castro idea.

Meanwhile, Arizona can keep shopping Upton to Texas. The bounty the Mariners nearly gave up for Upton should drive up the asking price, and that’s not good for negotiations wherein the primary problem was just how high the price seemed to be already. Still, it’s out there, Texas needs Upton worse than ever and Arizona has to feel like no better moment is forthcoming at which to leverage the rumor market and push the Rangers over the edge.

One way or another, Towers is creating a small advantage in trade talks by putting such lofty names out there. This has been a busy and bizarre winter in Arizona, and Towers’ biggest bet may be yet to come. Stay tuned.