Bob Dutton of the Kansas City Star speculated about a possible deal Saturday that would send Brian Bannister to the Yankees and Melky Cabrera to the Royals. On its face, the deal seems logical. It would allow the Royals to shift David DeJesus out of center field and into left, where his mediocre defense wouldn't hurt them nearly as much.
To quantify the defensive gain, DeJesus had a minus-12 RAA (runs above average) rating last year in 152 games. Cabrera rated plus-15 in 120 games last year, leading to an overall gain of plus-27 net runs prevented, possibly more if Cabrera plays every day.
Mark Teahen would then shift to first, replacing Ross Gload. Replacing Gload would be merciful, to say the least, given that he is replacement-level offensively and defensively.
From the Yankees' standpoint, the trade makes less sense. While Melky has been terrible at the plate this year (.655 OPS), he is still playing above-average defense in center field.
Their other center-field options are less than remarkable. I'm sure Brett Gardner could play center, but he's even worse at hitting than Cabrera (.396 OPS in limited time).
While it's obvious that any center fielder would just be keeping the seat warm for Austin Jackson, the trade for Xavier Nady and Damaso Marte made it obvious the Yankees are still engaged in "win-now" mode, so keeping an offensive black hole in center would not be a good idea.
Furthermore, Brian Bannister simply isn't that a good pitcher. Sure, he's fantastic to interview and knows more about statistics than most players. Unfortunately, that hasn't, and probably won't, translated into on-field success.
His stuff has always been fringy, and moving to the AL East will only make that more obvious. I'm not convinced that a guy with a DERA (defense-adjusted ERA) of 5.47 can survive the division.
In the end, I doubt this deal will happen. The Yankees have expressed interest in Greinke, and I'm sure that Dayton Moore has tried to steer the conversation to Bannister.
This trade would certainly help the Royals in the short term, but it probably wouldn't solve the Yankees' problems with the back end of their rotation. So I'd chalk this one up as a product of the deadline rumor mill and nothing more.