Brendon McCullum's recurring back problem has rendered him a doubtful starter for the first ODI to be played at Nehru Stadium in Guwahati on Sunday.

The wicketkeeper-batsman, who battled a similar back injury during the third Test in Nagpur, was seen in pain during their afternoon practice session on Saturday as he went off the field.

New Zealand skipper Daniel Vettori however has not completely ruled him out and said they would take a final call on Sunday morning.

Giving an update on McCullum's back spasm, Vettori said, "He just has an ongoing back problem that occasionally gives him back spasms, something that is being managed.

"We will take a call on him tomorrow morning. If he plays then he would (obviously) keep the wickets. No (other fitness worries) at this stage. We will see how Brendon is in the morning."

Vettori further said Martin Guptill will open the innings with Jamie How in case McCullum failed to recover.

Having hit a career best 225 in the second Test in Hyderabad, the New Zealand opener had a troubled back in the third Test as he batted at No 8 in the first innings.

McCullum incidentally is the in-form New Zealand batsman, topping their batting charts with an aggregate of 370 in the recently-concluded three-Test series.