He may have donned the gloves for the last time in international cricket.
McCullum delegated the task to Luke Ronchi and Tom Latham in the 50-over and 20-over matches respectively and, had it not been for a BJ Watling knee injury, wouldn't have taken the gloves in the tests.
It makes for a logical transition. McCullum remains one of New Zealand's best fielders. He underlined that with a catch at second slip off Michael Lumb from the two balls bowled by Mitchell McClenaghan in this morning's second Twenty20 international at the Oval.
The match was abandoned from that point due to rain.
"It's something that needs discussing," McCullum said after New Zealand secured a 1-0 T20 series victory to go with a 2-1 win in the ODI series and a 2-0 loss in the tests.
"[Being a specialist batsman] is an option if we can balance the team right.
"We've seen a few guys get chances with the gloves this tour. This T20 series was about Tom getting those opportunities. He did a good job, bar one stumping he was disappointed to miss [off Alex Hales]. He also chipped in with some runs. Obviously he's a player for the future but we need to work out where he fits in the shorter form, especially with Luke and BJ in the mix.
Coach Mike Hesson said they would give McCullum's role serious thought.
"If our next best batsman is in the side and they happen to keep it gives us a chance to build succession plans. Brendon is still more than capable keeping but when Martin Guptill's not patrolling the in-field we needed someone decent to replace him. It really depends on a potential keeper taking ownership of that top order batting role.
"Tom's more than capable with the gloves but he's not always keeping for Canterbury so it is a time-on-task thing really. He was in the squad as back-up for the tests but to debut with a Duke ball which swings a lot after bouncing was a bit unfair. We think he has a big future."
Hesson ranked his side as exceeding a pass mark after winning two out of three series.
"We can't do much about tonight's rain but the Champions Trophy was disappointing and we didn't scrub up at key times in the tests.
"However, when you play a quality side like England home and away over a five-month period and come out close to parity in many ways, it shows we're improving - particularly in coloured clothing. In the test matches we're not far away provided we can remove the odd bad session.
Hesson hinted he is looking at Guptill and Hamish Rutherford to open in all limited overs cricket.
"Martin and Hamish have sealed the opening spots in T20 cricket. [Hamish is] absolutely an option in 50 overs. That was an important reason for him to sign with Essex so he'd play 10-12 one-day 40-over games because he hasn't found the right tempo in 50-over cricket."
- Andrew Alderson of the Herald on Sunday
