If it's true that you should leave on a high, then Tim Southee and his test-playing compatriots are getting out at the right time.

The Black Caps crushed the West Indies at Bay Oval to take an unassailable lead in the three-match T20 series that finishes tonight. Southee won't be there – he's leaving along with Ross Taylor and Kyle Jamieson to prepare for the test series starting Thursday – but the skipper leaves safe in the knowledge that not only is his team well equipped for a clean sweep, but they are also building enviable depth.

The most obvious manifestation of the depth was the star of the show, Glenn Phillips, who was possibly on the outside looking in had Kane Williamson been available and had Colin Munro not chosen the glitz of the Big Bash over the more bucolic delights of New Zealand domestic cricket.

"He's got that X-factor about him," Southee said after the right-hander blitzed 108 off 51 balls then starred in the field with a direct-hit run out and a spectacular catch in the deep. "We saw how good he can be."

Such was Phillips' dominance over proceedings it was easy to forget that this series is his first in national T20 colours for more than two years. Easy to forget, too, that his first forays were not particularly successful, with a top score of 56 in 10 trips to the crease and a difficulty scoring off anything other than width.

"You never know when your next opportunity is going to come," Phillips said. "I was much more prepared for this time around.

"I started [my career] well, but I got the yips and had to take a step back to move forward again."

Describing himself as an "entertainer", Phillips talked about how New Zealand's long line-up allowed him bat like it was the "death overs" much earlier than usual.

There's still a bit of the unaffected, wide-eyed kid about Phillips, who turns 24 next week. Born in South Africa but raised in New Zealand since the age of five, the enormity of his achievement – he became just the fourth New Zealander to score a T20I century, set the record for the fastest, and set a world record for a third-wicket partnership with Devon Conway in the process – was still sinking in when he spoke immediately after the game.

"Oh my goodness. Absolutely unreal," he said.

For the first time all day he got something wrong. His innings was very real and it brought home the fact that for one of the rare times in New Zealand cricket history, there are genuine options outside the usual suspects.

Options, you'd guess, the West Indies would like themselves.

Captain Kieron Pollard was clearly frustrated by his side's lack of application, saying his team lost their way after the first 10 overs. Rather than a lack of fundamental skills, Pollard indicated that "mindset" was the biggest issue.

"That's not the standard we want to set," he said. "We need to be up for the fight."

They have one more match to show they can scrap.

Text by Dylan Cleaver, NZ Herald