Shane Watson sent a scare through the Australian camp when he was hit in the helmet in the MCG nets while preparing for the Boxing Day Test.

Allrounder Watson was struck by a short-pitched delivery from paceman James Pattinson on Tuesday morning and left the nets to receive treatment.

A Cricket Australia spokesperson said Watson was shaken otherwise okay.

In a lively session paceman Mitchell Starc also required treatment after being hit on the knee while batting.

Opener David Warner was a notable absentee from the session with his injured thumb but he is still expected to play when the third Test against India gets underway on Friday.