Attention Twin Cities drugstores: Stock up on antacid. In the biggest news of spring training so far, Minnesota Twins closer Joe Nathan has been diagnosed as having a torn ulnar collateral ligament in his right elbow. We've already looked at this from a fantasy perspective, so now it's time to analyze how this will affect the Twins.
Before today, the American League Central looked like a two-horse race between the Twins and the Detroit Tigers. With Nathan out, it's hard to see the Twins contending. Nathan, who turned 35 in November, was once again slated to be the steady hand at the back of the Twins' bullpen. He's saved at least 36 games in each of the past six years, and has been as good as just about any other closer in baseball during that time.
| Most saves (since 2004) | |
|---|---|
| Joe Nathan | 246 |
| Mariano Rivera | 243 |
| Francisco Rodriguez | 241 |
| Trevor Hoffman | 239 |
| Francisco Cordero | 225 |
So, how bad is the loss of Nathan? Well, there are two related, but separate, costs that Twins fans need to worry about. Manager Ron Gardenhire now has to figure out Nathan's replacement on the roster. He'll be a guy who, unless the Twins make a trade, otherwise would have started the year in Triple-A or on the waiver wire. Over the past few years, Nathan has consistently posted WARP3 scores around 6.0 (meaning he was six wins better than the average guy in Triple-A or on the waiver wire), and there's no reason to believe that this year would have been any different. Those six wins last year would have completely rewritten the story of the AL Central, from a neck-and-neck race to the end to the Tigers clinching in the last week and resting up before meeting the Yankees in the ALDS. Nathan makes that much of a difference.
| Highest Save Pct (since 2004 – min. 100 chances) | |
|---|---|
| Mariano Rivera | 93.1 |
| Joe Nathan | 90.8 |
| Trevor Hoffman | 89.8 |
| Jonathan Papelbon | 89.3 |
| Bob Wickman | 87.4 |
But then there's the other cost of Nathan's injury. Twins fans are probably not thinking about Nathan's direct replacement on the roster, but rather who will take over as closer in his absence. The likely candidates are Jon Rauch and Matt Guerrier, both of whom have their positives, but neither of whom is Joe Nathan. Over the past two seasons, Rauch and Guerrirer have each had a WARP3 hovering around 1.0. Fairly or unfairly, everything that happens in the ninth inning is magnified. Twins fans are used to having an elite closer to shut things down, and they now get to deal with the tummy ache that comes from knowing that a lesser pitcher is handling the last frame. There will no doubt be a few games where the new closer blows a lead and local sports radio lines will fill up with cries of, "Nathan would have saved that!" One thing to keep in mind, however, is that the average closer still converts roughly 85 percent of save chances, while Nathan has converted 90.8 percent of save opportunities for his career. If Guerrier and Rauch can convert saves at a league-average rate, Nathan's injury will be downgraded from a massive catastrophe to a medium-sized catastrophe.
| Best ERA (since 2004, min. 300 IP) | |
|---|---|
| Joe Nathan | 1.87 |
| Mariano Rivera | 1.90 |
| Billy Wagner | 2.16 |
| Francisco Rodriguez | 2.46 |
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I still think the Twins are favorites for the division, but I also thought they were a 90 win team before this. I think it's a tighter race now, but Guerrier is pretty capable and the return of Neshek and presence of Slama provide a couple other options that should keep the bullpen from becoming a complete liability.
But yes I do agree with pretty much everything you said. This surely will hurt the twins because its quite obvious Nathan was a dominant reliever, but this will not hurt the team nearly to the degree stated in this article or thought of by most twins fans.
--JRM
The guys who will take Nathan's leveraged innings are better than replacement level, so their WARP3 will increase with more leveraged innings if they simply repeat their overall performance level. When usage changes, WARP has very little predictive value for relievers (not that it had much to start with).
You have to take into account chaining in the bullpen. Nathan's replacement on the roster will be pitching very low leverage innings, meaning he'll have a negligible effect on the Twins' chances. What really matters are the other pitchers who are moving into more important roles.
Is this true?
I mean, I know a lot of people have accepted the idea. But where's the evidence?
Why did Pizza use WARP3 at all? BP has an in-house metric that makes way more sense to use, not to mention that all other reasonable estimates differ wildly from WARP3. I don't know what PECOTA projected since he's not on the depth chart anymore and there's no line on his PECOTA card, but you can still see his projected WXRL for 2009 and 2010 from the '09 PECOTA.
2009: 3.1 WXRL
2010: 2.6 WXRL
2.6, which just so happens to coincide with what Sky found. Here's the link:
Isn't chaining just a model for the optimal strategy assuming no replacements are brought from outside the club? I suppose it assumes that managers like to use roles instead of some kind of best-at-any-one time calculation, but either model would be a preferable alternative than just citing his WARP3. WXRL exists, right? 6 wins is just not what he's going to be worth. The Twins are paying him 11.25MM, which means we should expect the answer to be in the 2-4 win range. Sky's article on Insider using chaining found he'd be worth 2.6 WAR. CHONE projects him for 3.3 WAR. 6 is twice that and suggests he should be paid like Chase Utley.
Why did Pizza use WARP3 at all? BP has an in-house metric that makes way more sense to use, not to mention that all other reasonable estimates differ wildly from WARP3. I don't know what PECOTA projected since he's not on the depth chart anymore and there's no line on his PECOTA card, but you can still see his projected WXRL for 2009 and 2010 from the '09 PECOTA.
2009: 3.1 WXRL
2010: 2.6 WXRL
2.6 just so happens to coincide with what Sky found in the aforementioned article. Link here
http://insider.espn.go.com/blog/tmi-mlb/post?id=697&blogName=tmi-mlb&sort=oldest