Southee twice said he was running out of words to describe his long-time teammate, but the Black Caps skipper found a few to explain the experience of watching a batting savant.
“I’ve been very lucky to have a pretty good seat for all his career,” Southee said. “He gets into his batting bubble and I guess it’s his happy place.
“We joke about it, that he doesn’t like spending time with us, he’d rather spend it out in the middle. It’s just his pure hunger for batting, his pure love for batting.
“Not only in the middle but the time he spends in the nets. He’s just always looking for ways to improve his game. It’s no fluke that he’s as good as he is because he trains as hard as I’ve ever seen anyone, he hits more balls than anyone.
“He gets into that zone and he’s just a guy that you want in your team. He’s been an incredible member of this side and I’m sure it’s not going to end any time soon.
“There’s still plenty more brilliant things to come from one of our greatest ever.”
South Africa captain Neil Brand called Williamson “the best player in the world” and, five minutes before Southee entered the room, offered a strikingly similar description of his side’s conqueror.
“He just doesn’t leave his bubble,” Brand said. “When you watch him, he just stays there and focuses on the next ball. He really respects the game, never throws his wicket away and is always hungry to bat.
“We knew Kane was a big wicket and unfortunately we just couldn’t get him. He’s an absolutely amazing player.”
Williamson turned a challenging chase on a tricky pitch into another exhibition, supported ably by Will Young (60no). The No 3 was never hurried and offered no chances, blunting Dane Piedt after the offspinner had taken eight of the 13 New Zealand wickets to fall.
“The amount of times he’s done it, it’s no surprise,” Southee said. “But on that wicket we knew it wasn’t going to be easy, and he showed his class. We knew if someone could stick with him and he could show his brilliance throughout the day, it was going to be easy for us.
“He was tested with spin and pace and a challenging wicket at times. But as we’ve seen over the years, he came out on top. After the 12 months he’s had with injuries and setbacks and rehabs and coming back, it’s just phenomenal to see him go and do what he does.”
Williamson will now be on parental leave during next week’s T20 series against Australia, before returning for the two-test showdown. But before the Black Caps’ encounter with their old enemy, Southee intended to enjoy a maiden series victory over another, celebrating with the newly minted Tangiwai Shield.
“We’ve had some great battles over the years,” he said. “Test wins, they’re tough. We’ve seen that over the last four days and I’m just proud of the group to be the first ones to beat South Africa in a series.”