(Ed. Note: This piece was written prior to Nathan striking out the side against Kansas City on Thursday. No data or information from that performance is included in the below.)
You don't need the particulars, but here they are. Joe Nathan has a 6.57 ERA, 5.19 FIP, and -0.3 fWAR which are all the worst marks of his career since becoming a reliever more than a decade ago. He became a full-time, go-to reliever in 2003 and since then, this is his lowest strikeout rate, highest walk rate, and highest home run rate (all numbers entering Monday).
I don't have to tell you that translates into a career worst strikeout to walk ratio or differential. And it's not just the three true outcomes that we sabermetricians find so interesting, Nathan is also allowing the highest batting average against of his career and the highest slugging percentage since he became a reliever.
Dig deeper and his velocity is down, his movement is less deadly, and all of his pitches are less effective than they were in recent years. Batters are swinging at Nathan's pitches less often and making way more contact when they do, posting career worsts in those marks.
All three of his inherited runners have scored. He's struggling against everyone, but he has no answer for the 64 lefties he's seen, allowing a career worst .374 wOBA and turning in nine strikeouts and eight walks, which is by far the worst differential of his career. Righties are getting him too, but the damage isn't quite so bad.
The contact is harder and the fly ball balls are traveling significantly farther. You can't explain it away with bad luck. Everything Nathan is doing right now is going wrong. He's working down in the zone more often and those pitches are getting clobbered.
It's a startling collapse. Nathan was one of the best relievers in baseball a year ago and has consistently been one of the game's best for a decade save for a year and a half stretch while he recovered from Tommy John. Certainly, relievers are volatile and don't age well, but "one of the best" to "avert your eyes horrible" in the span of an offseason is hard to understand.
Ausmus has dismissed concerns about his age because it's not like he's a lot older than last year, but something is going wrong with Nathan. He went through a period of dead arm, but claims that's behind him and that he feels great. Color me skeptical. He's releasing the ball a touch higher than last year, which is the opposite from what you normally see with an injury, but an injury is the only thing that makes much sense.
Justin Verlander is going through some serious struggles right now, but even during his low points he flashes the good stuff from time to time and mixes in good starts. I can't remember the last time Nathan looked good on the mound. He's avoid disaster here and there, but his stuff and his command aren't there even when he does. There just aren't any good signs.
If you're looking for positives, Nathan has a long history of success in the major leagues and can draw on those experiences while also getting help from the very well regarded Jeff Jones. There's no way he'll be this bad all season, but every possible indicator is pointing in the wrong direction.
After every bad outing, the press asks Ausmus if he's going to remove him from the closer's role and so far he's held fast. You appreciate his unwillingness to overreact and the recognition that Joba is probably more valuable in a flexible 7th and 8th inning role, but you can only send this version of Joe Nathan out in close games so many more times.
It's strange to say that you're hoping for an injury, but you are. An injury makes sense and you can recover from an injury. If Nathan really is healthy, and he claims to be, then it becomes about survival for Tigers fans. The pedigree is better than Todd Jones, Fernando Rodney, and Jose Valverde, but if you can believe it, the results have been worse.
Neil Weinberg is a Senior Analyst for TigsTown. He is also the Founder of New English D, a contributor to Gammons Daily, and the Associate Managing Editor at Beyond the Box Score. Follow and interact with him on Twitter @NeilWeinberg44