Split the difference: Mike Pelfrey's revival due to revamped splitter grip

There have been a few surprises on this year's Minnesota Twins team. Right-hander Mike Pelfrey has been among the biggest.

One pitch is largely responsible for Pelfrey's revival, too.

It was during spring training this year when Pelfrey -- who missed most of last season with an injury -- talked with new bullpen coach Eddie Guardado about a particular pitch. Pelfrey knew that Guardado threw a split-finger fastball during his playing career and was hoping Guardado could help him revitalize his splitter. It was a pitch that Pelfrey had thrown since 2010, but it has lost its effectiveness over the years.

"I asked him, I said, 'Hey, what's the difference here, man? Do you have any advice or tips?'" Pelfrey recalls of the conversation. "He kind of tweaked the grip a little bit. I think it's made all the difference in the world."

Entering his start Monday against Cincinnati, Pelfrey has the lowest ERA in the rotation (3.06) and has logged the third-most innings among the starting staff. Of course, his health is a big reason for the resurgence as he's on pace to top the 152 2/3 innings he threw for the Twins in 2013, the year after having Tommy John surgery.

But the effectiveness of his revamped splitter, and the frequency with which he's thrown it, is the other piece of the puzzle. Pelfrey estimated he used to throw the splitter just three or four times in any given game before Guardado helped him change the grip. Now, it's used 20 or so times a start.

"It's made a pretty big difference," Pelfrey said. "It's kind of given me that changeup or secondary pitch that I've kind of been lacking."

The data backs that up. In 2013 -- Pelfrey's first year with Minnesota -- he threw the splitter just 8.5 percent of the time, according to FanGraphs. That was down from previous years, too; in 2010, he used it for 15.9 percent of his pitches and threw it 12.3 percent of the time in 2011.

So far in 2015, the usage of Pelfrey's splitter has jumped back up to 16.5 percent, the highest it's been in the six years he's had the pitch in his repertoire. Pelfrey still uses his sinker more than 50 percent of the time, but the split-finger fastball prevents opposing hitters from being as effective against his other pitches as they now have to worry about the splitter.

"It gives it something else to put in their head to kind of keep them off that fastball," Pelfrey said. "The results have been really good."

Pelfrey's splitter is several miles an hour slower than his normal fastball, giving it the appearance of a changeup with movement. The ensuing usage of it has been mostly positive. Batters are hitting just .210 against Pelfrey's splitter, and only one of the five home runs he's allowed this year has been off of that pitch.

He's also picked up three more strikeouts with the splitter (19) than with his fastball, which he's thrown 505 more times than the split-finger.

"I can only think of maybe a couple times that I've been beat on it this year," Pelfrey said. "I think for the most part it's been pretty good. It's been real successful."

That pitch is a big reason why Pelfrey should be receiving strong consideration to stay in the rotation when right-hander Erin Santana returns this weekend from his 80-game suspension. The Twins' starting staff as a whole has pitched well this year, so Minnesota will have a tough choice to make as to which pitcher will be the odd man out.

Thanks to the splitter, Pelfrey's spot appears safe. But he and the rest of the staff aren't taking anything for granted given what's coming at the end of the week.

"We understand he's coming back and he's going to be a part of the rotation when he gets back," Pelfrey said. "The guys in here, I don't think we try to worry about that. I don't think we try to play GM. One through five, I think all these guys, we're all throwing the ball great, throwing the ball well. Every night out, we're giving the team a chance to win. That's all you can ask."

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