Derek Jeter’s Bad Start

As is always the case here in New York, there is no shortage of discussion about the Yankees. For better or worse, 2010 has been an eventful season so far, affording reporters, analysts, and fans an abundance of topics to tackle. Here are the ten issues (in no particular order) that the fans and media are focusing on:

  1. Javier Vazquez’s woes
  2. Mark Teixeira’s annual slow start
  3. Phil Hughes’ emergence
  4. Robinson Cano’s breakout season
  5. Francisco Cervelli’s energy and surprisingly good offense
  6. Andy Pettitte’s elbow
  7. Curtis Granderson’s injury
  8. Alex Rodriguez’s low power output
  9. Mariano Rivera’s injury and infrequent use
  10. Brett Gardner’s unforeseen emergence as a genuine offensive threat

There is one potentially enormous development that is not on this list, and one that has begun to trouble me greatly. Simply put, there is a good chance we are seeing the beginning of Derek Jeter‘s decline. I think there are three reasons this has gone underreported. First, he’s Derek Jeter and this is New York. No one will suggest he’s declining until it becomes painfully obvious. Secondly, he’s hitting .270 and it’s May, so most will (wrongly) point to his still-solid batting average and (rightly) state that it’s still early, and conclude that he’ll snap out of it. Finally, the Yankees have too many other issues right now to warrant scrutinizing Jeter’s performance to death. Jeter’s play isn’t the most pressing issue right now, and I understand that.

But beneath the superficial “he’s still hitting .270 and it’s early” counter-argument, there are plenty of disturbing figures that suggest Jeter might be slowing down:

  • His walk rate sits at 4.6% – by far the lowest number of his career.
  • He’s swinging at 33.2% of pitches outside the strike zone – by far the highest number of his career.
  • He’s swinging at 52.4% of total pitches – the highest number of his career.
  • He’s seeing 3.54 pitches per plate appearance – his lowest number since 2004.
  • He’s making contact with 87.7% of total pitches – the highest number of his career (more on why this might not be a good thing in a minute)
  • He’s seeing the most fastballs since 2006 and the most cutters since he’s been in the majors (both fast pitches).
  • He’s hitting nearly four times as many ground balls as fly balls (3.83 GB/FB)
  • His line drive percentage (LD%) is 12.6% – by far the lowest number of his career.

The culmination of all these factors creates a narrative that isn’t all that difficult to imagine. It’s quite possible that pitchers have picked up on something – declining bat speed? – and are simply challenging Jeter with more hard stuff (fastballs, cutters) than in recent years. And while Jeter is making more contact than ever, the vast majority of the balls he has put into play have been grounders. When you add his inexplicably collapsing plate discipline with an inability to catch up to a steady diet of fastballs and cutters, well, you get a pretty dramatic decline in production.

Of course, I realize it’s May. But it’s also not too early for certain skills and data to be reliable predictors of future performance. I stumbled upon this bit of research a few months ago, and it’s pretty awesome. It’s quick summary of a much, much nerdier project that studied when sample sizes become reliable for certain statistics. According to the study, Swing%, Contact%, strikeout rate (K%), LD%, and P/PA all stabilize at or around 150 plate appearances. Jeter has 151 plate appearances. Walk rate (BB%), ground ball rate (GB%), and GB/FB tend to stabilize at 200 plate appearance, a benchmark that is right around the corner. So, it’s not too early to be concerned. At all.

I hope I’m wrong. I’ve been wrong before (cough Brett Gardner cough), and I’ll be wrong again. But once the dust settles, and Vazquez is pitching acceptably well, and Granderson is back, and Teixeira has settled in, and all that stuff, I think Jeter’s performance will be the lingering but unmentioned issue. This certainly bears monitoring, particularly with Jeter’s contract expiring at the end of the season.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: