Earlier this week, apparently as part of an ongoing campaign to irritate Yankees fans as much as possible, Alex Rodriguez said on the radio, “I want to 100% stay in New York. Period. That’s it.” He then intimated that if fans don’t stop booing him, he’ll exercise a clause in his contract that will allow him to become a free agent at the end of the year. The sharp, rumbling sound heard right after this interview was the sound of every Rodriguez supporter in the world — among whom you can firmly count this columnist — slapping their heads all at once.

Rodriguez is the best ballplayer of his generation, about as good in an off year as a truly great player like Derek Jeter is in his better years, and his main flaw is the lack of that quirk of character that makes most athletes completely oblivious to what’s going on around them. It’s painful to see such a magnificent player treated so badly by fans and the press because he’s sensitive, needy, and not an idiot. Being recognizably human shouldn’t make one susceptible to jeering and mockery. Since it does, though, Rodriguez should just not talk; continually exposing himself as something other than an automaton just makes the bad situation worse.

In addition to driving people mad, the latest Rodriguez flap brings the matter of that peculiar contract to the fore. Under the terms of his deal, Rodriguez can become a free agent at the end of this year for any reason, and the same clause holds at the end of each of the next two years if he isn’t being paid at least $1 million more than the next-highest-paid player in baseball. No one believes that Rodriguez could command a deal that would pay him more annually than the $27 million he’s due for each of the next four years as a Yankee. Still, Alfonso Soriano, who’s just five months younger than Rodriguez, signed a $136 million contract this winter. There’s no question that Rodriguez, a vastly better player, will have a real shot at his second $200 million contract if he does decide to opt out of his current deal.

This makes me think that Rodriguez will indeed opt out after this season, and not because of the jeers of Yankees fans, but because he will make tens of millions of dollars more if he hits the market at age 31 than he will at age 34. And not only is tens of millions of dollars is a lot of money, hitting the market also makes sense because Rodriguez has likely seen his best days.

It doesn’t take genius to see that Rodriguez is in a general decline. In his three years with the Yankees, only his 2005 MVP campaign has been in line with the years he routinely had when he was younger. In addition to sinking offensive numbers, his defense last year was downright awful, due largely, I think, to his carrying around too much weight in an attempt to offset slightly declining bat speed. A quick look at Rodriguez’s historical peers, though, shows that we may not have likely seen the beginning of his decline.

Isolating Rodriguez’s peers is tricky business, because he’s a historically great player and thus, by definition, unique. For a somewhat arbitrary measure, though, consider this. In baseball history, he is one of nine players who through age 30 racked up at least 6,000 plate appearances with a park-adjusted OPS+ of 140 or better while not playing first base or one of the outfield corners. (OPS+ measures onbase plus slugging percentage on a scale where 100 is average.)

Of those nine, four — Ty Cobb, Rogers Hornsby, Mickey Mantle, and Tris Speaker — aren’t truly comparable to Rodriguez, because they were much better hitters. Through his age 30, for instance, Speaker, the weakest hitter of the four, had an adjusted OPS+ of 166, about what Albert Pujols does in a typical year. Rodriguez, great as he is, isn’t quite of that class. All four of these men hit better after turning 30 than Rodriguez has in his career.

The other four, though — Eddie Collins, Eddie Matthews, Ken Griffey Jr., and Duke Snider — are all comparable to Rodriguez. As you can see in the accompanying chart, all of them lost a tremendous amount as hitters after age 30, and all but Collins proved rather fragile as well. The destinies of four other players don’t necessarily doom Rodriguez to a frustration-riddled second half of his career, but it’s an ominous sign that Rodriguez has spent most of his career not only playing a more demanding defensive position than any of these four, and racked up almost a full season of playing time more than any of them did through the same age. Rodriguez’s agent, Scott Boras, would no doubt present these facts as evidence of his exceptional durability, proof that he should get a lot of money. If I were a general manager, I’d be looking at these facts, and at Rodriguez’s declining athleticism, as warning signs.

Let’s say Rodriguez’s offense declines to the 120–130 OPS+ range of these other players, and that he stays on at third as a good but not exceptional defender. That’s very good, but it’s not great — guys like Aubrey Huff, Mike Lamb, and Corey Koskie have recently had seasons like that. I think Rodriguez will be better, but no one’s asking me to gamble enormous sums on it.

Right now, then, it looks as if it will probably be in everyone’s best interests for Rodriguez to opt for free agency in November, leaving the psychodrama aside. The Yankees wouldn’t risk paying the $48 million they owe Rodriguez from 2008–2010 for seasons like those out of Duke Snider’s painful decline; Rodriguez would be able to lock in a final, record-setting contract before seeing his value fall with a drop in performance. A lot can change in the next few months, but very little will change the dynamics at play. Even if Rodriguez belts 50 home runs, wins a Gold Glove, and single-handedly drags the Yankees to a world championship, that’s just going to increase his value and his incentives to sign a monster contract while he still can. One thing is certain — if Rodriguez, guided by a rational appraisal of his interests, files for free agency later this year, it’s going to be the yobs will take the credit for running him out of town. And that’s a shame.

tmarchman@nysun.com