Thursday, November 13, 2008

What have the Brewers lost in Salomon Torres?

At the surface, it seems like the Brewers have lost quite a bit. Torres saved 28 games for the Brewers with a 3.49 ERA and gave at least a little bit of stabilization to the later innings (although not a whole lot, as any Brewer fan can attest to) after the failure of the Eric Gagne Project. Torres retired last week, and this leaves the Brewer bullpen slightly naked at the back end. But really, did Torres have that great of a season? How many runs did he really save for the Brewers?

NOTE: Torres retired last week, but the Brewers picked up his '09 option, so if Torres decides to come back, he will remain a Brewer.

Let's take a look at a stat called tRA, from (check their glossary for this and more great stats) . tRA is a stat that is based on purely things that pitchers can control (walks, strikeouts, home run rates, etc., things that the defense doesn't effect) that is then normalized to the ERA scale.

Torres pitched 77.3 innings with a 4.63 tRA this year. Torres' controllable skills show that he was quite lucky to post such a high ERA. Much of this can be attributed to the Brewers defense, which was very good and by some metrics the best in the NL.

Let's convert this tRA and IP score into a number of runs saved above a replacement reliever (basically, any scrub from AAA, like, say Tim Dillard, who had a 5.99 tRA in his 14 IP with the Brewers this season). The formula for finding total runs saved above replacement is as follows:

EDIT: Turns out I was using the wrong value here. Should be 5.00 because we're looking at relievers.

(5.00 - (tRA))*IP/9.

Torres saved 3.22 runs above replacement (RAR) He definitely helped the bullpen. But let's compare him to some other relievers. Some other Brewers, some FAs, and some closers from around the league.

A couple Brewers:
Brian Shouse: 3.99 RAR
Carlos Villanueva (only as a RP): 11.53
(just for laughs)
Eric Gagne: -9.65 (and somehow, this guy is a type B free agent)

A few FA closers:
Francisco Rodriguez: 10.45
Brian Fuentes: 21.11
Kerry Wood: 20.97

And some other FAs, that some might classify as "F.A.T"
This doesn't mean Prince Fielder fat, but Freely Available Talent. Some of this depends on "Freely," because some of these guys are type B free agents, but either way, you might be able to get similar production to top-tier guys like K-Rod for far, far less money.

Jeremy Affeldt: 11.44 (previous contract 3M/yr)
Will Ohman: 8.94 (previous contract: 1.8M/yr)

And this guy is still the best reliever in baseball, even though everybody seems to have forgotten:

Mariano Rivera: 30.26

However, a big part of relieving has been ignored in this analysis. Closers, such as K-Rod and Wood and Fuentes pitch in more important situations, on average, than 6th or 7th inning guys like Villanueva and Ohman. So let's take that into account. Fangraphs keeps track of pLI, or the average leverage index for each reliever. Let's multiply the runs saved above average by pLI in order to take a look at a little truer number of runs saved. Also, let's look at their runs saved multiplied by 1.93, the average closer pLI (with closer defined as any reliever with 20+ saves in 2008).

For some reason, I can't seem to get rid of all these spaces so you'll have to scroll down a bit for the table.

EDIT: Fixed it!

PITCHER tRA IP RSAR pLI RSAR*pLI RSAR*1.93 WAR (normal) WAR (pLI) WAR (1.93)
Torres 4.63 78.3 3.22 2 6.44 6.21 0.32 0.64 0.62
Shouse 4.3 51.3 3.99 1.08 4.31 7.7 0.4 0.43 0.77
Villanueva 3.25 59.3 11.53 1.09 12.57 22.25 1.15 1.26 2.23
Gagne 6.9 45.7 -9.65 1.72 -16.59 -18.62 -0.96 -1.66 -1.86
Rodriguez 3.59 66.7 10.45 2.54 26.54 20.17 1.04 2.65 2.02
Fuentes 1.97 62.7 21.11 2.01 42.43 40.74 2.11 4.24 4.07
Wood 2.11 65.3 20.97 1.99 41.73 40.47 2.1 4.17 4.05
Affeldt 3.68 78 11.44 0.56 6.41 22.08 1.14 0.64 2.21
Ohman 3.63 58.7 8.94 0.88 7.86 17.25 0.89 0.79 1.72
Rivera 1.11 70 30.26 1.92 58.09 58.39 3.03 5.81 5.84

This shows us some pretty interesting things. First of all, Mariano Rivera is amazing. 5.84 wins above replacement at closer. Second of all, if guys like Jeremy Affeldt or Carlos Villanueva could maintain the type of raw production they get in the roles they have now, they could be very effective closers, at the level of a guy like Francisco Rodriguez.

Of course, this has to be taken with a grain of salt. We don't know if these players will thrive if thrust into a closer role, and it's possible that in these lower leverage situations that they aren't facing the same quality of hitters that closers are. But it does tell us that managers CAN use them better than they are being used, and that you don't necessarily have to spend 10 million dollars to get a guy that's a couple wins above replacement (or, in the Brewers case, -.882 WAR), and that Brewers GM Doug Melvin may have plenty of options available to bolster the bullpen with besides expensive guys like Wood and Fuentes.

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