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The Story of Bobby Jenks

Bobby Jenks is out for the rest of the year and the rumors have begun to fly. See ESPN, the Examiner, RotoWorld, MLBTradeRumors, and even Bob Nightengale chime in with their belief Jenks will get traded this offseason.

Entering his second year of arbitration, his steady save totals should augment his $5.6 million salary to the point where he may not be the best use of Kenny Williams’ resources. He was, for example, only worth $1.9 million this year.

His story is also not one of consistency. Generally speaking, he was lucky last year despite poor underlying stats, and this year he’s had the reverse happen. It might just be the story of small sample sizes in the end, but can a team like the White Sox afford a closer that costs more than $7 or $8 million?

Much was made in 2008 of the precipitous decline of Jenks’ strikeout rate. Surely he must be suffering from an arm injury, we all said. No one goes from striking out almost a batter per inning to 5.55 K/9 in one year without something being wrong, right? Especially with his fastball velocity down almost two MPH off its peak. Well, not so much. He got through the year with a sub-3 ERA, perhaps thanks to his career high 57% groundball percentage, and also thanks to a little luck (.261 BABIP).

Fast-forward to this year and the secondary stats all normalized to his career rates (8.27 K/9, 2.70 BB/9), and his fastball regained a mile per hour. Unfortunately, his luck turned too. While his BABIP (.298) stayed the same, his other batted ball statistics went south. The real ‘unlucky’ part of his game concerns home runs. Despite a reasonable fly ball percentage (33.1%), he’s giving up a home run and a half this year thanks to a distorted home run per fly ball rate (17%, 9.6% career).

So now the portly (6’3″ 275 lbs) closer is on the DL with a calf strain and the team will get to audition their possible replacement in Matt Thornton. What can we expect, and does Thornton have the stuff to be the closer in 2010?

Non-traditionalists will look at his numbers and give an unqualified thumbs up to Thornton’s candidacy. 330+ innings into his career, his strikeout rate is good overall (9.37 K/9) and excellent recently (over 10 K/9 the last two years). In his last 134 innings, his walk rate has been under 2.55 BB/9, which is also excellent. He’s actually had two straight identical seasons with great underlying numbers. Sure, his groundball rate took a step back this year, and his flyball rate went in the wrong direction, but can you really argue with two straight FIPs under 3?

He has the fastball of a closer (95+ MPH), a good slider (neutral by linear weights over his career), he gets people to reach (reach% over 25% for the last four years), and they don’t make great contact even when the ball’s in the zone (79.7%). What’s not to like?

Ah, there’s the rub. Thornton has blown 10 saves against two saves in the last two years and for some the thought is that he can’t handle the pressure. Are there actually great relievers that can’t be closers? This may need a more comprehensive look, but as anecdotal evidence I submit to you Heath Bell. Bell had 12 blown saves against his first two saves despite good underlying numbers that don’t even look as nice as Thornton’s do now. Sure, Bell may be slowing down a little recently, but he sort of blew through that blown saves problem this year, wouldn’t you say?