Just as I was putting the finishing touches on a post about how important it is for the Yankees to re-sign Jorge Posada, no matter the cost, the word came down that Posada had indeed re-upped with the Bombers to the tune of $52.4 million over four years. Posada came within hours of hitting the market, as free agents are able to sign with any of the 30 major league teams starting today.

I’ll get to the length and cost of Posada’s contract (which just inches past the matching $52-mil/4-yr deals given Johnny Damon and Hideki Matsui prior to the 2006 season) in a moment. First a word on Posada’s value on the field.

Put as simply as possible, here’s what the average major league catcher hit in 2007: .256/.318/.394.

Now here’s Posada’s 2007 season: .338/.426/.543 in 144 games.

Need I go on?

Okay, here are the top VORP totals by catchers in 2007:

Jorge Posada: 73.4
Victor Martinez: 55.0
Russell Martin: 46.1
Joe Mauer: 30.2

Notice how Posada’s total is nearly as high as the third and fourth best catchers combined? Notice that the other three players are a minimum of three years from hitting the market (Mauer and Martinez are signed through 2010, and Martin will be under team control through 2011).

Let’s do this with 2006, shall we?

Average C: .269/.329/.416
Posada: .277/.374/.492 in 143 games

VORP Leaders, Catchers:

Joe Mauer: 66.9
Brian McCann: 54.8
Victor Martinez: 47.8
Jorge Posada: 38.0

Sure, Jorge didn’t dominate the field in 2006 like he did in 2007, but notice the trend: Jorge outdistances the average catcher’s production by a laughable margin, while the VORP leaders at the position are once again Jorge and three guys who won’t hit the market for another three years.

To be fair, there are four other catchers from the 2006 top-20 who are currently free agents. Here are their 2007 seasons:

Michael Barrett: .244/.281/.372, 101 games
Paul Lo Duca: .272/.311/.378, 119 games
Mike Piazza: .275/.313/.414, 83 games (0 games caught)
Jason Kendall: .242/.301/.309, 137 games

By the way, Lo Duca’s 2007 season above was good for the 19th best VORP by a catcher this season, which means 11 teams did a lot worse at the position Actually, 12 did worse, as Lo Duca’s backup, Ramon Castro, finished 12th. Meanwhile, Lo Duca and Castro combined had less than one-third of Posada’s VORP total.

Any questions?

Okay, sure, Jorge’s age. Posada’s 36 and will be 37 in August and 40 by the time his new contract expires. Here are all of the catchers who have caught 130 or more games in a season at age 36 or older in the history of major league baseball:

Al Todd, 1938, 132 games at age 36
Bob Boone, 1984-1986, 137, 147, and 144 games from ages 36 to 38
Carlton Fisk, 1985, 130 games at age 37
Benito Santiago, 2001, 130 games at age 36
Brad Ausmus, 2005, 130 games at age 36

That’s it.

Here’s the list of catchers who have caught 130 or more games in a season at the age of 36 and posted an OPS+ above league average:

Carlton Fisk, 1985, 115 OPS+

That’s it.

Posada has caught 130 or more games and posted and above-average OPS+ in every year of the current decade, but something will have to give soon, and the Yankees obviously would prefer it to be the games caught rather than the OPS+.

Here’s the good news. Posada has already had the greatest season by a catcher age 35 or older in the history of the game (Gabby Hartnett’s 1937 season was the previous standard), so he’s already an outlier. Expecting him to have a productive season in 2008 despite his age is not unreasonable given the strength of his performance the last two years and the fact that September, a month when most catchers (including a younger Posada) tend to run out of gas, was Posada’s best month in each of those two seasons. What’ more, Posada’s production is so far out in front of the other available catchers that he’ll still be valuable to the Yankees even in decline. Plus, a large part of that production is due to his patience at the plate (his worst OBP in a season in which he’s had more than 15 plate appearances is .341, his worst since becoming the Yankee starter was .352, and his career OBP is an outstanding 104 points higher than his career batting average), which is a skill that should survive the eventual loss in power he’s sure to experience over the next four years.

After the 2008 season, the Yankees will part way with Jason Giambi (buying out his $22 million option for a steep, but acceptable $5 million), clearing extra at-bats for Posada at DH and first base (Posada, who began his professional career as a second baseman, has played 18 major league games at first base and posted a solid, if small-sample, 117 Rate2). Of course, the competitive advantage that Posada provides decreases with each additional game started at first base or DH, but given the alternatives and the outside chance that Posada indeed could be the second coming of Carlton Fisk, who caught 106 games and posted a 134 OPS+ at age 42, (it’s long been thought that Posada’s late conversion to catching could buy him extra years behind the dish at the end of his career, that theory appears to be becoming a reality), it’s well worth the gamble.

As much as giving a catcher a multi-year deal that stretches into his 40s sounds like insanity on the surface (I’m sure I was among those who laughed at the $40-million/4-year deal the Red Sox gave Jason Varitek, who’s eight-months Posada’s junior, two years ago), the length makes a certain amount of sense. To begin with, the Yankees had hoped to keep the contract to three years, but it apparently took a fourth year to get Posada signed, which was a concession worth making per the above. Following the third year of Posada’s contract, Martinez and Mauer will hit the market (unless they receive extensions in the interim, of course). After Posada’s contract is up, Martin and McCann will hit the market (again barring extensions). Meanwhile, the Yankees have Francisco Cervelli (a career .277/.379/.390 hitter in the minors who should begin his age-22 season with double-A Trenton in 2008), and Austin Romine, the strong-armed high-school catcher the team took in the second round of this year’s draft, working their way through the system. There are no worthwhile catchers available now, but by the time Posada’s ready to relinquish the position, there could well be a glut of them.

And, of course, there’s something to be said for watching a home-grown player finish his career where it started while earning a place in the new Monument Park and, just maybe, a place in the Hall of Fame*.

*Milestones to watch: Posada needs 82 homers to become the seventh, or eighth if Ivan Rodriguez gets there first, catcher with 300 career home runs. Jorge’s hit 83 over the past four years, so it’s a long shot, but it’s possible. If Jorge hits 18 homers in 2008 he’ll move into the top-10 all time for catchers by tying Gabby Hartnett