Australian fast bowling legend Glenn McGrath has backed Shane Watson and predicted a return to form for the struggling all-rounder in the fourth Test at the Sydney Cricket Ground (SCG) beginning Tuesday.

Watson has endured an extended lean phase with the bat, failing to score a Test century in 12 months.

Criticism regarding the No.3 batsman has intensified in the ongoing Test series against India after he failed to get going with the bat.

"I've always had faith in Shane, I think he's a quality player, he's a quality all-rounder and I think with Mitchell Marsh being injured he's an even bigger player," McGrath was quoted as saying by The Sydney Morning Herald Saturday.

"It would be nice to see him go out and get a hundred here and a few wickets so that's my prediction for this Test match."

Watson himself admitted his shortcomings and said he felt the pressure steadily building on him.

"I feel I'm under pressure when I'm not scoring runs at any stage. If I'm not performing, of course I'm under pressure," the 33-year-old said Saturday.

"The thing I think about the most is to just be able to contribute to the team, not whether I'm playing or not. It's more so just being able to contribute to the team and feel like I'm not a passenger.

I do really want to be there to be able to contribute with bat and ball, that's what I think about the most."