Joe Nathan is showing major signs of decline at age 39

Joe Nathan has been one of the best closers in baseball for a decade, saving 354 games with a 2.85 ERA, but at age 39 he’s finally showing signs of decline in his first season with the Tigers.

Nathan saved 43 games with a 1.39 ERA and 73 strikeouts in 65 innings for the Rangers last season, which convinced the Tigers to give him a two-year, $20 million contract as a free agent, but now he’s got a 6.86 ERA with four blown saves and two losses.

Nathan continues to miss a fair number of bats with 20 strikeouts in 21 innings, but he’s walked 11 batters and served up four homers. And perhaps most worrisome is that his average fastball velocity is down to 91.4 miles per hour compared to 94.0 mph in 2012 and 92.2 mph last season.

Predictably, the struggling closer told Jason Beck of MLB.com that he’s confident about turning things around:

This isn’t the first time I’ve gone through a funk and come out the other end. I’ve dealt with two injuries. I’ve pitched much worse than this, trust me. I’ve pitched much worse than this in Triple-A, got sent down to Double-A, got my butt back to the big leagues. I think having dealt with that, having--not the confidence, but at least the experience of knowing I can come back through this stuff definitely helps.

He’s right about coming back from a lot in his career, including Tommy John surgery in 2010 at age 35, but unfortunately Father Time remains undefeated and Nathan’s struggles appear to be more than simply bad luck or a rough patch. As a Twins fan who got to see Nathan dominate for a half-dozen years I’d love to be wrong, though.

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