Originally Posted by Aim For The Chains
Sounds like you need to close your shoulder and make sure your wrist/arm is not turning up/over. You don't want your wrist or shoulder to roll over at all, specially during your extension which will cause massive "oat" if you were previously not extending correctly and add that in-- yet your throwing planes are out of wack so those lines will be exaggerated even more.
you can check this by seeing if the palm of your hand is facing the ground or turns up through your extension.
When you say to close my shoulder, what does that mean?