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The Mets signed Rey Sanchez to a 1 year deal.

It only took them about 5 years, but the Mets finally realized that you don't need to pay $5 mill a year for a good defensive shortstop that can't hit.

Rey Sanchez replaces Rey Ordonez as New York's shortstop and he will easily outproduce Ordonez, offensively and defensively, for a fraction of the price.

Rey Sanchez spent last year as Boston's second baseman after serving as a full-time shortstop with Kansas City and Atlanta the previous 3 years.

Sanchez is a phenomenal defensive player with great hands and outstanding range.

Injuries limited him to only 107 games last season with Boston, but Baseball Prospectus rates him as 12 runs above the "average" second baseman and 32 runs better than a "replacement level" second baseman defensively.

Those are some very good numbers for a guy that played only 107 games, but his numbers at shortstop the previous 3 years are even more impressive.

Year     FRAR     FRAA

1999      58       28

2000      51       21

2001      72       43

"FRAR" stands for Fielding Runs Above Replacement and "FRAA" stands for Fielding Runs Above Average.

Basically, a "replacement level" player is someone that is pretty crappy, thus easily found, and an "average" player is just that, average.

There are a lot of problems with defensive stats and I am far less confident in using them as evidence of a player's worth than I am with offensive stats, but they are still very useful and extremely intriguing.

In a given year, Rey Sanchez is about 60-70 runs better than a replacement level shortstop on defense and about 25-40 runs better than the average shortstop.

His hitting is very sub par, but let's switch things around and see how it effects how we view Rey Sanchez...

Let's say that instead of being 40 runs better than the average shortstop on defense, he was 40 runs better on offense.

And let's say that instead of being sub par with the bat, he was sub par with the glove.

There is no doubt that a shortstop that is +40 on offense and -10 on defense is considered a heck of a lot better than Rey Sanchez.

Like I said, defensive stats have a lot of problems and they are far from being as reliable as offensive metrics, but they still have a lot of value.

Baseball Prospectus also lists a stat called "Wins Above Replacement Position" which basically calculates how many wins a player is worth to a team over a readily available player at his position, after taking into account both offense and defense.

While Sanchez was a full-time SS from 1999-2001 he was worth 6.6, 4.6 and 7.3 "WARP."

Last year, because he was injured and didn't play shortstop, he was "only" worth 3.8 "WARP."

Those numbers are more impressive than you might think.

From 2000-2002, Derek Jeter was worth 6.3, 7.2 and 5.9 WARP.

From 2000-2002, Omar Vizquel was worth 5.7, 3.9, 6.2 WARP.

For the sake of furthering this discussion towards some sort of a point, let's toss out Sanchez's 2002 because he was injured and wasn't allowed to play his "best" position defensively when healthy.

Here are Sanchez's last 3 years as a shortstop, along with Jeter and Vizquel's 2000-2002:

Player          WARP1     WARP2     WARP3     TOTAL

Jeter            6.3       7.2       5.9       19.4

Sanchez          6.6       4.6       7.3       18.5

Vizquel          5.7       3.9       6.2       15.8

I am certainly not going to sit here and say that Rey Sanchez is a better player than Derek Jeter.

However, I think that defensive contributions are vastly under-examined and players like Rey Sanchez (legitimately awesome defensive players at key positions) are worth a whole lot more than most people think they are.

Bill James once said that much of what we see as "pitching" is actually "defense" and the more I read about Voros McCracken's work on Defense Independent Pitching Stats and the more I read about the value of defense, the more I start to believe it.

Defensive superstars like Rey Sanchez are extremely underrated simply because their contributions come largely on defense, which is an area that is really tough to measure accurately.

But, runs are runs, whether they are added with a player's bat or subtracted with a player's glove.