Now that the Super Bowl is over and sports fans can turn their gaze southwards, toward Florida and Arizona, we are going to have to find a group of underrated, hard-working everymen to laud even as we overlook them. Sorry, Saints offensive linemen, your brief moment of hagiography is over. Before their knees begin to creak and their backs begin to spasm, let us consider for a moment the path of a catcher. The catcher aesthetic is gritty, dirty, achy, and inglorious. Not pretty-in the face or with the bat? No problem, catchers, Nichols’ Law of Catcher Defense has got your back, offsetting your failure in other, less tangible ways.

Obviously, Joe Mauer Hasn’t Read Much Vonnegut

But what about the rare orchid, as captivating as it is delicate, that dares rise above the swampy waters? Catchers who can hit and field the position well are one of the scarcest commodities in baseball. Part of the explanation is that catchers who hit well are often moved off the position in order to guarantee a spot in the lineup. Todd Zeile and Craig Wilson are classic examples of players who shifted to infield corners shortly after reaching the majors because their bat developed faster than their skills behind the plate.

This raises an interesting problem. Recall the defensive spectrum, which describes the general difficulty of each position and suggests in which direction players can move as they age. No doubt familiar to most readers, the defensive spectrum begins at one end with shortstop and runs all the way to designated hitter. But where along this line do catchers fit? In the 2009 National League, catchers hit .255/.325/.385, which of course includes the traditional benefit of intentional walks, as subtracting them reduces the OBP to .315. Shortstops, on the other hand, hit .268/.327/.396, and removing their intentional walks drops their OBP to .321. This at least must be indirect evidence that catchers are harder to find than shortstops, mustn’t it?

But it’s here that the catcher position represents a sort of discontinuity in the defensive spectrum. Most catchers, when they move off the position, transition either to first base (like Carlos Delgado) or to third base (like Zeile or Brandon Inge). Occasionally, an athletic oddity will move to second base or center field, but such things appear not to happen in the absence of Hall of Fame talent. The strange thing is that catchers, when they move, drop to the middle of the defensive spectrum. However, if they manage to stay at the position, they represent an improvement on what is often the league’s least productive spot.

That means productive catchers who can stay at the position are perennially hot prospects. A player like Joe Mauer, the first catcher to win two, never mind three, batting titles, is one of the most valuable commodities in the league. When speculative reports surfaced last week that Mauer and the Twins were close to signing a long-term deal, many wondered about his ability to stay behind the plate. Other than his size (6-feet-5, 220 pounds) and the everyday rigor of catching, there is nothing in particular to suggest that Mauer can’t stick it behind the plate. And yet, the sheer terror he inspired in the hearts of pitchers in the American League Central perversely lowers the chances he has to become the greatest catcher of all time.

Last season, Mauer recorded 28 games as the designated hitter, which was a career high. Mauer missed the entire month of April due to injury, but returned to the league like Tim Raines returning from collusion. Paradoxically, the better Mauer gets as a hitter, the less likely he may be to remain a catcher. The flexibility of the designated hitter position only increases the chances that Mauer will play fewer and fewer games behind the plate. It is possible that the DH helped mitigate the injury that just robbed us of witnessing the greatest catcher season in history, but it may also prop up Mauer’s replacement level going forward, since each game he plays at DH could be played by Jason Kubel or Jim Thome or some other competent hitter without defensive virtue.

Perhaps a more disturbing specter for Twins fans is that Mauer loses the potent bat. If any Minnesotans have gazed into Sean Forman’s palantir at the bottom of each Baseball-Reference page, they’ll notice that Mauer’s third-most similar player through age 26 is Jason Kendall. However, the last word from Deadly Accurate gives comparables of Terry Kennedy, Mike Scioscia, Victor Martinez, and Ed Bailey. That’s three guys from the John Madden Everyman’s School of Gritty Sports Athletes plus another in Martinez, who is already spending a significant amount of his time without a chest protector.

By way of impossible comparison, Johnny Bench‘s fifth full season of 1972 was his career year. He boasted a .336 EqA and a 10.5 WARP3. Mauer, missing a month of his fifth full season in ’09, notched a .346 EqA and an 8.8 WARP3. (That’s 9.1 rWAR for Bench and 7.9 for Mauer, if you’re curious.) You can chalk the difference up to Bench’s status as the greatest catcher in history, or to the flukiness of Mauer’s injury, or to the time spent at DH, but the fact is Mauer could not yet cast off the weights put on him by his innate gifts and the Handicapper General. While Mauer has tremendous promise going forward (PECOTA projects 142 games and a 5.3 WARP for 2010), he may never again have a chance like he did in 2009.

Won’t Somebody Think of the Children?

There is currently a bumper crop of top catching prospects chomping at the bit for a chance to receive in the majors. Among them, Buster Posey, Jesus Montero, Jason Castro, and Carlos Santana lead the way. Yet, before any of these prospects have won a starting job in the major leagues, half of them seem doomed to exile from behind the plate. Montero’s size (like Mauer, he’s 6-5, but heavier) leads scouts and our own prospect expert Kevin Goldstein to all but guarantee a move to first base or designated hitter in the near future with the Yankees, despite apparent improvement in his formerly execrable defensive skills. The simply logic is that Montero’s bat is ready well before his glove, and like Wilson or Zeile, that will seal his fate.

Posey, on the other hand, finds himself bafflingly blocked by the eldest Molina. The Giants may settle this problem of their own creation by trying Posey at first base, although they remain adamant that Posey is their catcher of the future. Unlike Montero, nobody questions Posey’s ability to field the position. Instead, circumstances have conspired to push Posey down the rabbit’s hole and defensive spectrum simultaneously.

Santana, whose bat is nearly ready for the Indians‘ lineup, is really hampered only by some of the ancillary aspects of catching, like English language skills and game-calling. Luckily for Santana, these are the sort of last-mile problems typically solved in short order by everyone except cable companies. As for Castro, the merry band of mischief makers that replaced Brad Ausmus‘ production behind the plate in Houston appear not to be any serious impediment to his development. In short, Castro, the one most agree has the worst bat, is almost certainly the one most likely to become the everyday major-league catcher.

Question of the Day

If I told you a player made it all the way to Double-A playing catcher, but I didn’t tell you anything else about him, how likely do you think he would be to stay at the position? Essentially, all four of the young prospects considered above have done just that. In other words, how strong is your prior probability and how much weight should be put on posterior evidence when evaluating young catchers?