There is no greater freedom then the style in which a batter uses as he awaits a pitch. Each one is unique to every hitter to ever play the game, whether a high school player or a Major League All-Star. In the Major Leagues, some players break the conventions of what they were taught while developing their skills as a child. These players have molded unique, strange, and sometimes downright bizarre batting stances. Check out this video "E:60 The Art of the Batting Stance".
The stance is just a starting point, whats consistent is are the "Hitting Absolutes". In this article I will talk about 5 absolutes that are needed to execute proper swing mechanics.
1. "Rear Knee" - The power portion of the swing is fired through the hips, so the rear knee must stay inside the ankle, as it holds energy in the hips. That tension in the hips is held until front foot landing. 2. "Maintain a Level Head" - Once the hitter lifts their front leg to stride, there is no vertical head movement. The head must stay level with the eyes focused on the pitcher, until the stride leg reaches its peak. Once the batter's stride has reached its peak, they will move into his forward momentum towards the pitcher. Watch this video of Josh Donaldson do both of these absolutes perfectly.
3. "Linear/Forward Momentum" - With forward momentum, the knee on the rear leg, the belly button and the head, should all move toward the pitcher. Once a batter has finished forward momentum, the front leg should land bent, front foot pointed at pitcher or on a 45 degree angle. The weight distribution should be at a 50/50 balance or 60/40 on the front foot. This allows for proper sequencing of the kinetic chain working from the ground up. For more info check out my article Front Foot Landing "Closed or Open?". 4. "Launch position" - The batter must load their upper body using the scapula muscle of the rear arm and have their hands in a loaded position by the rear shoulder at front foot landing. The shoulders are still square to the pitcher. This allows a slight delay of the upper body creating torque and separation. Looking at Jose Bautista at front foot landing, has bent front leg with open foot. His hands are at the rear shoulder.
5. "Rotation" - Once in the launch position the batter is now ready for the unloading of the torque and separation. The batter must rotate to hit the ball keeping his hand close to the rear shoulder until slightly before contact of the baseball. Watch Mike Trout's rotation and how he doesn't get any "extension". The goal of the "contact point" is not to extend the arms, but have them bent.
Hope this article was helpful and dont forget to #StayInSequence.