Well, this is pretty much inevitable. According to MLB.com's Joe Frisaro the Marlins will listen to trade offers on Giancarlo Stanton. They're being careful to say that they're just following a policy of listening to all offers and aren't actively shopping their
only remaining Major Leaguer best player, but there's no real reason to even acknowledge that publicly if you aren't willing to part with him for a plausible offer. The Marlins tore up the core of their team with that big trade with Toronto in November, and although they could keep the super cheap Stanton around as a reason for people to buy tickets, it also makes sense to dangle him for a super-package of prospects to continue to aid the rebuilding process. Plus, Stanton took his displeasure with that trade public on Twitter, and Jeffrey Loria is the sort of petty tyrant who doesn't take kindly to being challenged by the hired riff-raff.
Not that you should get your hopes up about seeing Stanton in pinstripes any time soon. As one of the game's premier power hitters at the ripe old age of 23, and with another pre-arbitration season in his future, Stanton is one of the three or four most valuable trade chips in the game, and will require a hefty package that includes multiple high ceiling young players who are either already in the majors or knocking on the door step, and the Yankees simply don't have those kind of assets at their disposal right now. Barring some sort of crazy multi-team agreement, the Yankees aren't going to get anywhere close to acquiring Stanton, no matter how willing to let him go the Marlins are.