Arms Collapsing in Back Swing

[Elmer]

I have developed a habit that seems to show up at the end of  a round.
The last 2 weeks it has shown up on the last 3 or 4 holes. 
Not sure if I am getting worn out, tired or just sloppy?

my right arm collapses on driver-wood-long iron shots. This causes my right elbow to bury into my side and my swing becomes some what baseball like. The result is usually a quickly closed clubface resulting in a short duck hook.
I have been trying to work on keeping my arms away from my body and making a wide arc swing. 
In the past this type of swing has resulted in the best contact, ball flight and least amount of trouble.

Can any point to any drills that can get this swing back in my back.
Any suggestions for a pre-shot routine to reinforce this swing would also be appreciated. 

[klineka]

https://thesandtrap.com/forums/topic/35195-shorter-probably-better-swing-keep-the-right-arm-straight/

 

 

[billchao]

It might be fatigue causing you to stop turning and just swing with your arms. One of the causes of the trail elbow collapsing can be a natural instinct of where in space the hands should be and then trying to get them there with only arm action.

[iacas]

It could be a lot of things. For example, in trying to stay wide, you could be staying wide early and then your arms have to bend, so they create a lot of momentum and bend a bunch late.

Or a number of other things.