England head coach Brendon McCullum believes out-of-form Jonny Bairstow will come good in the Fourth Test against India.

Bairstow is under serious pressure heading into the must-win clash, which begins in Ranchi on Friday with the series score 2-1 in favour of the hosts.

The 34-year-old batter registered scores of 0 and 4 in the tourists' 434-run Third Test defeat in Rajkot last week, having not passed 37 in any of his last six innings.

But McCullum plans to put his arm around the Yorkshireman rather than replace him.

The New Zealander, 42, said: "People are entitled to their opinion, good, bad or ugly. It's up to us whether we want to listen to it or not.

"We know a top-quality Jonny Bairstow is as good as anyone in any conditions.

"We've got to keep giving him confidence and block out a lot of the external noise, keep him really present and focused on what he's trying to achieve.

"I will spend a bit of time with Jonny and remind him that he's such a wonderful player. 

"And not because you're trying to get a performance but because he's a good bloke and you want to make sure he's enjoying himself.

"I'm sure Jonny will come good."

Bairstow's team-mate Joe Root has also been criticised for his shot selection in the first innings of the last Test when he reverse-ramped Jasprit Bumrah straight to second slip.

Critics argue Root does not suit England's Bazball style but McCullum's approach was again to encourage rather than chastise.

He said: "People see a shot like that and go, 'Joe Root is struggling to deal with this new regime'.

"His impact on the game is still very, very significant. 

"Imagine if this becomes the norm for Joe as well, with the talent he possesses and the history he's got. Then what's the ceiling?

"Do we want just a normal Joe Root or do we want an even better Joe Root? How many games are we going to win if that happens?"