Wait, what? You can't be serious...
Let me make one thing clear at the very beginning. I do not "want" to trade A.J. Pollock. I enjoyed enormously watching him play center-field this season, and he would have been the most valuable player on the vast majority of teams in the majors. Take him off the Diamondbacks and we are a worse team, no doubt about it. But the two rules which should be the golden ones of trading in baseball are: a) Sell high, and b) Deal from positions of strength to address your positions of weakness.
There's no doubt that the Diamondbacks need starting pitching, and top-notch starting pitching at that. It seems unlikely they will be able to compete on the open market for the Zack Greinkes and David Prices this winter, and may end up having to overpay even for a second-tier agent - the case for and against John Lackey, for example, has already been made. The alternative is to trade for such a starter. But much though we'd like to believe otherwise we're not going to get one for Peter O'Brien and a gently-used Aaron Hill. No, if we want quality for the top of the rotation, the cost will be significant.
Indeed, if we want an All-Star caliber pitcher, it's not unreasonable to expect that we'll have to give up an All-Star caliber player in return. We had two All-Stars on the 2015 Diamondbacks, and even I would not be so delirious to suggest, even as a joke, trading the other one. [The San Diego Padres may feel differently] But Pollock for a genuine ace starting pitcher? Hmm. It has to be said, our outfield has enough depth that the benefit would likely outweigh the cost. And do we think Pollock will really be a seven WAR (7.4 bWAR, 6.6 fWAR) player going forward? If not, then his trade value will only go down, as his years of control decrease and age (28 next month) and cost go up.
Ok, I'm slightly intrigued. Who'd be interested?
Based on 2015 performance, he'd be an upgrade on just about any team bar the Angels [and, as an aside, I expect the draft this year to focus heavily on the new market inefficiency, center-fielders named after fish] But for some, Pollock would be an enormous improvement over what they got at the position this season. To try and figure out who'd be a good fit, I present to you the Pollock Trade Quotient or PTQ. It's based off this chart, showing how many wins above average teams were at each spot. We're looking for teams with strong SP and weak at CF, so the PTQ is WAA from starting pitching divided by two, minus the WAA from center. The top four teams by PTQ are as follows
1. Cardinals (PTQ 6.6). This was definitely a position of weakness for the Cardinals, though they still managed to win 100 games, even with most games being started in CF by John Jay, who hit .210 with a 56 OPS+. The current plan appears to be Tommy Pham, a 27-year-old rookie who did well enough, but still has less than 200 major-league PAs to his name. They certainly have pitching, with the likes of Michael Wacha or Carlos Martinez names who could provide a long-term solution in the Diamondbacks' rotation.
2. Nationals (5.0). They'll be looking to reload rather than rebuild, under new manager Dusty Baker, and Michael Taylor was unimpressive in center for them, batting .229 with a 72 OPS+. The main problem here is a lack of cost-controlled pitching they could give up in exchange. Of those who started more than once, only Joe Ross, brother of the Padres' Tyson Ross, is younger than 27. While his numbers are decent, he showed signs of fatigue at the end of the season, and it would be a stretch to call him All-Star caliber at this point.
3. Dodgers (4.7). This is where the PTQ does fall apart, mostly because a large chunk of the Dodgers' score is due to Zack Greinke who is no longer a Dodger. Young pitching isn't exactly their forte either, though I have heard they've got this guy called Clayton something, who's showing promise... In CF, they'll probably give Joc Pederson every chance to fail, even though the drop-off in his performance would more accurately be called a plummet, as he hit below the Uecker Line from May on. And they have too many OF as is, Pederson being joined by Carl Crawford, Andre Ethier, Yasiel Puig and Scott Van Slyke.
4. Indians (3.6). I was surprised to realize that Cleveland actually finished above .500 this season. Not much of that was, however, due to their center-fielders, which started off as Michael Bourn and ended as Abraham Almonte, a 26-year-old who has been traded every year since 2013. They do have some decent arms, led by Corey Kluber, who won't be a free-agent until at least 2020. Danny Salazar and Carlos Carrasco are both also under long-term team control, rather than being rental pieces.
I also want to throw in the Mets, because we've seen what a powerhouse of young pitching they became in the playoff, riding the arms of Jacob deGrom, Matt Harvey and Noah Syndergaard all the way to a largely unexpected National League pennant. If only they had had a real center-fielder like A.J. Pollock, rather than Juan Lagares with his .289 OBP, six home-runs and complete inability to hit right-handed pitching (career OPS = .627). Let's just deal an All-Star for an All-Star, swap deGrom for Pollock and call it a day, shall we?
Oh, you're dreaming...
Probably, yeah. But one of the more sensible things Kevin Towers said, was that there was no such thing as an untouchable player. The Diamondbacks should be open to listening to offers for Pollock, although the bar is going to be very, very high. We're also in the positive position of not "having" to trade him: if nobody comes along with an offer we want to accept, that's perfectly fine as well. But with alternatives in the outfield of Ender Inciarte, David Peralta and perhaps an O'Brien/Yasmany Tomas rotation for right-handed balance, Pollock might just be the most valuable trade-chip the Diamondbacks have this winter.