Posted by: Jack Mankin (MrBatspeed@aol.com) on Tue Nov 20 08:46:20 2007

Hi All

Before my analysis of Teixeira's inside/outside mechanics, there is one more piece of "overload" information I would like to bring to your attention.

We normally think that during shoulder rotation, both the lead and back shoulder are rotating at the same rate - about 90 degrees of rotation each. However this is not the case. The way each of the shoulders are hinged (close to the spine) allows each to rotate about 75 degrees (60 inward - 15 rearward) independent of the other shoulder or torso rotation. I have referred to this inward rotation as the inward "shrugging" of the lead-shoulder to set up the launch position.

During rotation, the added inward shrugging and un-shrugging of the lead-shoulder, means that while the back-shoulder rotates about 90 degrees, the lead-shoulder is rotating about 150 degrees. This added rotation of the lead-shoulder is an important factor in both power for the swing and adjusting for pitch location.

Depending on pitch location, the degree of un-shrugging of the lead-shoulder can pull the lead-hand (and knob) an added 10 to 12 inches inward - or away from the plate. As I stated, this is a very important factor in altering the hand-path for inside and outside pitches. On inside pitches, the shoulder fully un-shruggs pulling the hands inward away from the plate. On outside pitches, less un-shrugging leaves the hand-path wider.

Below is a mark-up of the Rose clip showing the difference in lead and back shoulder rotation.

Rose shoulder rotation comparison

Jack Mankin