England's Jonny Bairstow has come in for criticism after scoring just 102 runs in three matches in India but coach Brendon McCullum said it was important to show faith in the batter and that he has no plans to drop him for the fourth Test in Ranchi.

Bairstow's highest score in the series so far was 37, posted in the opener in Hyderabad. He scored four runs in England's 434-run thrashing in the third Test in Rajkot and was trapped lbw for a duck in his first innings, making him the player with the most ducks against India in Test cricket with eight.

The 34-year-old's struggles with the bat prompted former England captain Alastair Cook to say he should be dropped from the side but McCullum is keen on helping him rediscover his form.

Asked if Bairstow would make his 99th Test appearance in Ranchi this week, McCullum told reporters: "I haven't even seen the wicket. But I'd anticipate Jonny would be playing, yes."

McCullum acknowledged that Bairstow had underperformed during the series but said he deserved some time to get back on track.

"I'm not blind but he's done so well for us and he's had such an impactful career ...," McCullum said.

"So from our point of view, we've got to keep on giving him confidence and block out a lot of the external noise as well and keep him really present and focused on what he's trying to achieve, and I'm sure Jonny will come good.

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

India lead the five-match series 2-1, with the fourth Test getting underway on Friday.