What happened to Derek’s OBP?

I don’t have much credibility on the subject of . At the end of 2010, when Jeter was a free agent, we polled the writers here at TYA about what kind of a deal Derek deserved. Pessimistically I wrote that Jeter deserved a one year deal. Derek had just put up a 94 wRC+ season, by far his worst numbers since his cup of coffee season in 2010. He looked to be in severe decline. Apart from his 3,000th hit, what could he offer the Yankees?

Boy, was I wrong. After going 3-5 on Sunday, Derek is now batting .318/.359/.422. Entering Sunday’s game his wOBA was .337 and his wRC+ was 108. While none of this is as good as the .313/.382/.447 that Derek has posted over his career, the Captain obviously has a lot more left in the tank than a hater such as myself predicted. Bluntly put, Jeter is putting up a great season at an advanced age, one that no one predicted. I only have one question: What happened to that extra 20 points of OBP?

Although Derek has often had the reputation of being a bit of free-swinger, the truth is that he walks a decent amount, hence the career OBP above .380. Derek’s career walk rate is 8.8%, which isn’t up there with, say, , who has a career walk rate of 13.3%, but combines with Derek’s natural ability to put the ball in play for hits to make for a deadly, all around hitter.

Typically, in a season such as this, when Derek has an AVG above .310 his numbers would suggest that his OBP would be above .370. Instead, Derek is putting up an AVG right around his career level, but his OBP is more than twenty points lower. Sure enough, his walk rate this season is 5.3%, which is a career low, including Jeter’s abridged 1995 season.

Before I go any further I want to say clearly that I love these results. The Derek of old was a better player than this Derek, but the Derek of old was ten years younger as well. I’m happy to take less OBP from Derek if it means he can keep his overall line up the way it is right now. My purpose here isn’t to criticize. It is simply to point out that Derek has changed his approach. Who says you can’t teach an old dog new tricks?

Generally speaking, Derek is putting the ball in play more this season. His walk rate of 5.3% is a career low, but he’s also striking out less. His 12.1% K rate is also a career low. He’s putting the ball in play more, yet he’s maintaining a .349 BABIP, which is right in line with his career totals. That is a natural recipe for more hits, even if it comes at the cost of a few walks.

Sure enough, Derek’s changed approach comes across in his batted ball profile. His 66% ground ball rate is a career high, while his 13% fly ball rate is a career low. While this isn’t going to result in a lot of home runs, ground balls tend to go through for more hits than fly balls. That is precisely what’s taking place.

Finally, Derek is once again showing success against the fastball. In 2010 Derek was worth just 2.6 runs against the fastball. He improved that in 2011 to 6.2 runs, but it was still well below his career norms. (For example, in 2009 he was worth a stunning 28.1 runs against the fastball.) A good rule of thumb is that the better hitters hit well against the fastball. This is the pitch batters see most often, and eventually all pitchers find themselves in fastball counts. When that happens a hitter has the advantage, if he can hit the fastball. It also holds generally true that the ability to hit the fastball goes away as a player declines. Given all this it is a pleasant surprise that Derek has already produced 12.1 runs against the fastball coming into Sunday’s game.

It has been said that Derek is playing ball like a young man this season. I disagree. Derek as a young man was a different player, a more patient hitter with quite a bit more power. (People overlook the fact that Derek has hit 249 homers in his career.) Instead, Derek is playing like a new man this season. Something in his approach has changed that is giving him more success against the fastball. While he’s not hitting the ball out of the park the way he used to he is consistently putting the ball in play for hits. While this means more singles and fewer walks than he used to generate, the net results so far has been a return of his high average and the best season he’s put up since 2009. Here’s hoping it continues.