New Mechanics, Reliance on Slider Hurting Jonathan Papelbon

Evan Brunell@evanbrunellFeatured ColumnistMay 29, 2009

CLEVELAND - OCTOBER 18:  Closing pitcherJonathan Papelbon #58 of the Boston Red Sox delivers against the Cleveland Indians during Game Five of the American League Championship Series at Jacobs Field on October 18, 2007 in Cleveland, Ohio.  The Red Sox won the game 7-1 making the series 3-2.  (Photo by Jim McIsaac/Getty Images)

There's been no shortage of events this season that have taken us by surprise. David Ortiz, of course, is the big one. But what about Jason Varitek being in double-digit home runs before June? Tim Wakefield being our steadiest starter to date?

Here's one that's taken us by surprise: Jonathan Papelbon looking mortal. His 2.57 ERA is the highest its been as a closer, and superseded only by his 2.67 ERA as a rookie, when he served as a starter and reliever.

His FIP, however, would easily be the highest of his career as it sits at 4.60. He's still striking out well over a batter an inning and is limiting the number of hits he's given up, but it's the free passes that have changed everything.

Papelbon has an eye-popping 4.71 BB/9, this after a career low 1.04 last year. Papelbon has tried to swat away the concerns:

Jonathan Papelbon made some changes to his delivery for this season, the purpose of which was to transfer wear on his arms to his legs.

"Every outing and every day, I'm adding just a little bit more confidence to my delivery and approach and my game," Papelbon said. "Just slowly starting to get better with consistency. When you have consistency, you're going to not have to grind as hard every inning."

"The wear on my arm has gone from there to my legs," Papelbon said. "My legs are taking the brunt of the force now, which is going to enable my arm to stay healthy."
"I've changed my delivery, kind of added a little bit more power to it," Papelbon said. "When you make adjustments in this game, you're going to have to take the good with the bad, and maybe right now I'm throwing a little bit more pitches than I have in the past. To me, I'm still not overworking myself because by changing my mechanics, it's able to take some of that pressure off my arm. So throwing 15 pitches the old way is the same as throwing 25 the new way."

In addition to changing where he sets his hands (from his waist to his shoulder), Papelbon is driving more with his lower body.

Even the slightest adjustment in baseball can make things go awry. So far, that's been the case.

Papelbon struggled a bit in early April with his mechanics but ripped off a nine-game scoreless streak before May 23 and 25 sent his ERA from 0.90 to 2.57. He gave up two runs in each of those appearances despite issuing just one walk total.

While Papelbon's BB/K ratio has improved in May, the batting averages of his opponents have perked up. That would seem to suggest that he's not quite there yet in terms of effectiveness.

He's giving up line drives and fly balls at a greater clip than ever before as a closer. That, naturally, comes with a downturn in grounders which tend to be all but automatic outs.

Papelbon is throwing 17.5 pitches per inning, up from a career 15.8 percent. That's a lot, and can add up over time.

The question is, then, whether these hiccups will eventually straighten themselves out or if this is a product of the new mechanics that supposedly will add longevity to Pap's career. But if the new mechanics boot him out of the discussion as one of the best closers in the game, is it worth it?

People have said that Papelbon relies far too much on the fastball, pounding it away. This is true, to an extent. He's actually throwing less fastballs than last year. Last year, he tossed fastballs 81.2 percent of the time and saw decreased effectiveness as a result. Thanks to Fangraphs' Pitch Linear Weights, we can see this.

I won't go too in-depth as to what pitch linear weights are, but in a nutshell, each pitch thrown has an effect on the probability of a run being scored. If you throw a ball, the probability of a run being scored increases, no matter how negligible. A strike decreases the chances of a run being scored.

Papelbon's fastball was extremely effective in 2007, with a 3.29 weight per 100 pitches. This year, that's down to 0.66. In other words, his fastball isn't game-changing anymore. It's just another pitch.

He's incorporating his slider more than he ever has, throwing it 10.4 percent of the time. He's never been higher than 6.5 percent as a pitcher. He also has brought his change-up back after taking a two-year hiatus from it.

After a career high 19.7 percent usage of his split-fingered fastball in 2006, he's been decreasing his reliability on it to a career-low 10.2 percent so far this year.

For whatever reason, Papelbon and Co. aren't interested in leveraging his splitter as a weapon. Maybe it's because it puts too much strain on his arm or is too inconsistent. Maybe it's not separated enough from his fastball Whatever. The change has been made.

As a result, batters are laying off his pitches far more and making him work for his outs. Batters are swinging 10 percent less, which is a huge differential in baseball. For comparison, a career .300 hitter who gets 500 at-bats and gains an extra 10 percent in hits in one season hit .333.

So what has Papelbon done so far this year? He's tweaked his mechanics, moved away from his splitter and increased reliance on his slider. Based on the numbers, the changes haven't been for good.

I'm a bit concerned about Papelbon's slider being the reason why righties are hitting Papelbon better than they ever have. Righties are hitting at a .261/.364/.421 clip. For reference purposes, from 2006-8 righties hit .178/.215/.254 (lefties hit Papelbon slightly better).

A slider thrown by Papelbon will move away from a right-handed hitter. Hitters can use that natural path to flick the ball the opposite way. If it's an inside pitch, hitters can gear up more effectively for a home run because as they swing, the slider will veer into the sweet spot as opposed to shaving the handle off.

I'm prepared to give Papelbon a couple months more to work the kinks out, especially since he's still being effective—just not as effective. If August rolls around and he's still giving up walks and hits at a higher clip, though, I'll be calling for either a return to his old mechanics or more reliance on his split-fingered fastball.