Williamson was dropped by wicketkeeper Sarfraz Ahmed on 26 off Faheem Ashraf in the 22nd over. That egg needed catching. Beyond that reprieve, Williamson's innings was flawless.
"The ball was holding in the wicket a bit, and you come to a point where you either address it sensibly or do something silly.
"Today I was a little more sensible in accepting they bowled well for a long period. I felt we were fortunate to get above 300. The wind was tough, and maybe that's why we gained an upper hand."
Williamson's innings highlight came against Faheem in the 20th over. He skipped down the wicket and, balancing between his front and back feet, punched a ball through extra cover. Such poise would have left Joseph Pilates breathless.
"He [Faheem] was bowling really well because it was holding up a bit and the way he was angling in meant he wasn't missing much, so I wanted to change his length.
"It was pleasing that it came out the middle and helped grab a bit of momentum."
Selflessness was also evident from the captain. Williamson eased a ball backward of point on 96 and scampered back for a second run. He was just inside the popping crease when wicketkeeper Sarfraz Ahmed removed the bails. The skipper is not apathetic to three-figured milestones but, in the heat of the moment, an extra run for the team ranked as a higher priority.
His 90-run partnership with Nicholls off 80 balls was probably the most valuable in the innings.
The pair came together at 198 for four after 34 overs and ticked over the strike by finding plenty of spaces without taking any undue risk. That prepared New Zealand for a blast at the death.