Jason Bay Sucked in 07. Why?

Here’s what I wrote prior to the beginning of the 2007 season;

“I’d take Jason Bay ahead of the reigning AL MVP anyday. Jason has had no protection over the past three years, and yet he’s still produced. With Bay likely hitting in front of LaRoche and a healthy Nady, he’s more likely to see some pitches in the strike zone. Look for 40 HR, plus is usual 100 Runs, RBI’s, and walks.”

If you’re still with me after that bonehead call, let’s try to find out what exactly happened to Bay in 2007.

The first thing that you’ll notice in my comment is the optimism towards Bay finally getting protected in the line-up. Unfortunately, LaRoche was awful for the first three months of the season. I hardly think that this can be the cause of Bay’s woes. With that said, I do think that this could have been a tiny cause of Bay pressing at the plate. Tiny. Let’s move forward.

Outside of the huge drop off across the board in power & OPS numbers, Bay had a huge shift in his SO/BB ratio. For the two season prior, Bay averaged close to 100 BB a season with about 150 K. In a total reversal, he went down to 59 BB and basically maintained his preposition to the strikeout.
As a believer in spring training stats being a predictor of plate approach, I checked back into Bay’s spring past.

In at least 2006, Bay didn’t mind taking a walk in the training games. In 2007, he was all about hacking, walking only once vs 16 strikeouts. Sure, it’s only spring training, but that signals a bias towards swinging vs working the count.

I know that this is a very simplistic analysis, although the numbers really don’t lie. So can this be summed up to a simple change in plate approach for Jason? I originally though so until I dug a little deeper.

The following hit charts are for home games only, as that’s all I can get from mlb.com at the moment. The charts are only set up to show doubles (black d) and home runs (blue h). The first chart is for 2006, with the second for 07.

In 2006 the majority of Bay’s doubles were either down the line or up the middle. His long balls were, for the most part, pulled to the ally or hit up the middle.

Jumping into the 2007 hit chart data, Bay is almost devoid of pure pull home runs & doubles, instead opting to take his extra base hits up the middle or the opposite way.

A slowing down of his bat speed is a logical explanation for the high strike out total and lower power numbers. I’m not 100% sold on bat speed as an explanation behind the decrease in walks.

Exactly why did his numbers take a nose dive? I can’t exactly pin the tail on the donkey right away on this one, although it does appear to be an issue of plate approach. Whether his spray data tells us that his bat is slowing or that he was intentionally looking to go the other way is up to the reader to decide. Either way he had a sub par 2007. I’ll be very interested to see what approach Jason takes come spring training 2008. Will he be back to working the count or hacking away? I’ll also be checking the spray charts at the end of April to see if he’s getting around on the ball.