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March 25, 2008 | By Alex Eisenberg

What Happened to Jason Bay?

One of the big mysteries of the 2007 season was the decline of Pirates' OF Jason Bay. The question everybody has is how it happened.

Was it injuries? Bay did battle knee discomfort for much of the 2007 season and was coming off arthroscopic knee surgery from the previous offseason. However, Bay has said his knee only bothered him when playing the field and had no effect on his season. Did he just have a down year? Another possibility. Perhaps he has just begun his decline as players with his skill set seem to decline at a faster and earlier rate.

Lets begin with his numbers from the last two seasons:

2006 - .286 BA, .928 OPS, 15.2 BB%, 27.4 K%, .246 ISO, .338 BABIP, 15.6 LD%, 40.4 GB%, 3.8 IFFB%, 18.8 HR/FB%

2007 - .247 BA, .746 OPS, 9.9 BB%, 26.2 K%, .171 ISO, .298 BABIP, 16.5 LD%, 38 GB%, 9.8 IFFB%, 11.4 HR/FB%

What do the statistics tell us?

1. Loss of power - 75 point loss in ISO-power and a decline in the percentage of fly balls that became HRs (18.8% to 11.4%)

2. Softer contact - lower batting average and a lower BABIP (batting average on balls in play)

3. Decline in plate discipline - he may not have seen the ball all that well out of the pitcher's hand or he felt uncomfortable hitting with two strikes due to a drop in confidence

4. Similar batted ball data - Bay hit a similar about of GBs and FBs, while his LD% went up slightly. His IFFB% moved more toward the league average.

Jason Bay during 2006 seasonJason Bay slumping during 2007 season

The clip on the left is of Bay in 2006 and the pitch is a 92 mph fastball that drifts back over the middle of the plate. The clip on the right is of Bay during the 2007 season and the pitch is an 89 mph fastball with a little sink that also drifts back over the middle of the plate. I've done my best to synchronize the clips to contact, but if the clips seperate from one another, just refresh the browser and the clips will start over again.

Both pitches were hit for HRs between left and center field.

So what differences do you see if any at all?

My first general observation is that he seems a bit more together in 06. The bat is closer to his body and the arms have a little bit more of a bend to them. What I specifically want to look at is his stride into foot plant. It looks as if the 07 Bay reaches his front leg forward as he lifts and drops his foot into foot plant, while the 06 Bay seems to glide into foot plant without reaching.

Jason Bay's hip rotation in 2006Jason Bay's hip rotation in 2007

The two clips above are of Bay from toe touch into foot plant.

They both seem to carry their wieght forward a similar distance. However, the problem is with his timing and efficiency. Look at Bay in 06...see how at the very end of the clip, the point in which his foot plants, his hips have begun to rotate and the hands are about to come with it? Bay's 2006 swing has much better efficiency of the power-producing components that go into a swing. Use the belt buckle as an indicator. The chain of events that lead to Bay's swing look much more smooth and efficient in 2006 than 2007.

As each version begins to rotate their hips, which looks to have the more violent/aggressive rotation of their hips? Which version puts more force into their swing?

Jason Bay hip rotation in 2006Jason Bay hip rotation in 2007

To me, it looks like the 06 version has a much more powerful hip rotation. Bay's 2007 swing doesn't build up as much momentum and force as his 2006 swing does. To see a powerful hip rotation, all one has to do is look at what Prince Fielder does. I think part of the problem is that he extends that front leg forward and hurts his ability to efficiently rotate his hips like he does in 06.

Also, if you go back and simply look at each version before he swings, you see a lot of unnecessary movement in the 07 clip. The bat is the key indicator to look at.

Getting Jason Bay Back On Track

Well, I first think this goes beyond mechanical problems. If you read certain quotes from Bay during his slump, you will hear him talk about a feeling of uncomfortableness. He said something to the effect of finding himself in an 0-2 hole and having the feeling the at bat was already over. His confidence is the first thing he must correct. When the pitch is thrown, the batter has less than a second to see the ball, determine pitch type, determine the pitch location, and decide whether to swing the bat or not. There is no room for thinking about mechanics. The more a player thinks, the worse they do.

Once he fixes himself mentally, he should go to work on his mechanics. He first needs to shorten his swing a little. Get into a more compact, more together position like he had in 2006. Bay should then work on his stride into foot plant so that he efficiently maximizes the power of his swing.

Of course, this is all easier said than done. We'll revisit this article later to see what adjustments, if any Bay makes.


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Credit for sources used in this article: MLB.com

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