Yet one of McCullum's appealing cricketing traits is his ability to veer a conversation away from self and back towards team.
He may quietly find huge pleasure in personal performances, but he hides it pretty well.
The result is that, for all his 1000-plus test runs in 2014 - another New Zealand record, including four big centuries - you have to dig about to find him talking about personal goals.
He admitted to a couple of brief flashbacks when he went into the Basin dressing room, but he talks far more freely about what his team achieved in that test, in the year, than whatever he may have done to contribute towards it.
"That doesn't really float my boat," he said yesterday when asked about whether he had his eye on records, such as Martin Crowe's 17 test hundreds, six ahead of McCullum.
"It's nice to tick off some milestones along the way but for me it's about team success, and that was what was so enjoyable about last year."
Ask his special moment of last year and the answer will surprise; the series win against the West Indies in the Caribbean.
"Whilst I didn't get many runs it's still probably the proudest moment I've had playing for New Zealand because you saw guys performing in tough conditions.
"Different guys stood up and you know the team is travelling well when you see that happen."
McCullum began his year with 224 against India at Eden Park, a key element in a thrilling victory; he ended it with a staggering exhibition of hitting, 195 against Sri Lanka last week.
So how does he know when, or if, to move his batting up a gear?
"I guess it just unfolds sometimes," he said. "Throughout my career I've tried to play in that manner. Having a lot more trust in my defence [helps].
"If you know your defence is capable and you're able to bat a period of time then your attacking game can unfold, rather than having to attack because you don't have confidence in your defence. It's nice to start making contributions."
Sri Lanka, having been put through hoops by McCullum at Hagley Oval, have plans to handle him over the next few days at the Basin.
Captain Angelo Mathews wasn't about to divulge them but said patience was the key against McCullum.
"When a guy smashes you all over the place and gets almost a double hundred it's quite hard to set fields because he was not orthodox. He was going for his shots," Mathews said.
Both captains are likely to send their opponents in should they win the toss on a green, grassy Basin strip.
The look is nothing new, but the appearance can sometimes deceive. The pitch will be hard, have bounce but should give batsmen room for expression from the second afternoon.
New Zealand will be unchanged if Tim Southee is over an ankle injury. Kane Williamson's sore shoulder is unlikely to stop him playing.
Sri Lanka will be strengthened by the return of left arm spinner Rangana Herath, the world's leading wicket taker in 2014. They are also expecting far more from their batting champion Kumar Sangakkara, who had a rare double failure, 6 and 1, in Christchurch.
"When he fails it's a coach's nightmare," Mathews said.
"You have to throw at him for hours and hours. He's a very hard worker and he's desperate to go out and get some runs, so I'm sure he will do it tomorrow."
Mathews confirmed Sri Lanka's batsmen have been using two-piece balls in their preparation. Two piecers swing more than the four piece.
"It's just to counter the swing and try to get used to it and so make you feel better.
"That's what we're going to expect because Southee and [Trent] Boult are bowling like that and we've got to try and push them back."
On which subject Mathews was emphatic; Southee and Boult sit on a par with the likes of Dale Steyn and Morne Morkel, the South African pace champions.
"They're one of the best attacks. They are taking a lot of wickets with the new ball, and striking with the older ball. They've certainly got skill and are certainly right up there."
