Ken Rosenthal / FOXSports.com
The A's Jason Kendall and Yankees Jorge Posada rank 1-2 in games started at catcher since 2000, according to STATS, Inc.
Not surprisingly, both are in decline.
Clubs routinely ask too much of their starting catchers, in part due to a dearth of quality backups. The teams in best shape at the position either boast a star regular or quality tandem.
Take the Reds, who led the majors in on-base/slugging percentage at catcher last season; they started Jason LaRue in 104 games and Javier Valentin in 58.
The Blue Jays have formed perhaps an even stronger duo, signing free-agent catcher Bengie Molina to complement last year's starter, Gregg Zaun.
And while the Red Sox rely heavily on Jason Varitek, they generally use a different catcher for knuckleballer Tim Wakefield, a pattern that enabled them to limit Varitek to a relatively modest average of 122 starts over the past four seasons.
Kendall, 32, is nearly two years younger than Varitek, but his collapse last season is Exhibit A when demonstrating the cumulative effect on catchers who are overused.
Since 2000, Kendall has averaged 141 starts per season at catcher. Last season, his first with the A's, he produced his worst offensive season — and still made a career-high 146 starts.
Kendall's .321 slugging percentage was the lowest in the majors among hitters with enough at-bats to qualify for the batting title. In 601 at-bats, he failed to hit a single home run.
The A's backup, Adam Melhuse, hit 11 homers in 214 at-bats in 2004 — and for some inexplicable reason, batted only 97 times while Kendall struggled through '05.
"We're going to give Jason more of a rest this year, no question," A's general manager Billy Beane says. "Melhuse is a pretty good offensive player who deserves to play."
Posada, who turns 35 on Aug. 17, responded well to increased rest last season; he made 123 starts, his fewest in five years as a regular, and had a big September.
In the past three seasons, however, Posada's overall OPS has declined from .923 to .881 to .782.
That latter figure still ranked Posada sixth among major-league catchers in '05, but the question is whether he will become this year's Bernie Williams, an older Yankee who goes into marked decline.
If Posada starts 81 games, he will trigger a $12 million option for 2007. Early in the off-season, the Yankees considered adding a quality catcher who would help them escape the option. But in the end, they signed a backup, Kelly Stinnett, to replace John Flaherty, projecting Posada to play approximately the same number of games.
"Clearly, he's declined, but he's still at the top of the offensive heap," Yankees G.M. Brian Cashman says. "Quite frankly, we're more worried about how to replace Jorge Posada in two years rather than preventing him from vesting an option. He's one of the premier catchers in baseball offensively and defensively. That's a fact."
Still, there's no denying that as the seasons pass and innings mount, the unique rigors of playing catcher often transform an offensive threat into a less imposing hitter.
Johnny Bench was 29 when he produced his last 100-RBI season, Gary Carter 32. The Tigers' Ivan Rodriguez was a mess last season at 33. The Padres' Mike Piazza was 33 when he had his last big season in 2002.
The likelihood of offensive decline is less daunting for defensive specialists such as the Astros' Brad Ausmus and Giants' Mike Matheny — or for a catcher who can save his body by playing another position, such as the Orioles' Ramon Hernandez, Venezuela's first baseman in the World Baseball Classic.
The shortage of catchers, however, remains a problem throughout baseball. The Dodgers, Braves and Angels are perhaps the only clubs deep in young catching. One scouting director says that out of the top 100 prospects in this year's draft, only three or four are catchers.
All of which leaves the Jays in a potentially enviable position. Molina, 31, is likely to play more than Zaun, 34; his superior throwing will come in handy against the Angels, Devil Rays and other base-stealing opponents. Zaun, though, won't go to waste; his career .342 on-base percentage is 33 points higher than Molina's.
"Zaunie will play even more than he thinks he's going to play," Jays G.M. J.P. Ricciardi says. "We'll use those guys to our advantage."
An advantage few other teams can claim.
Ken Rosenthal is the senior baseball writer for FOXSports.com.