New Zealand beat Pakistan by 119 runs.
The performance was another blueprint of what is required for World Cup success.
Big runs equate to big pressure.
New Zealand's total was the second highest at the venue, justifying the decision to bat.
It's hard for any team to cope when the required run rate looks like an inflation graph from the 1970s.
The bowlers had initial difficulty controlling the Pakistani openers Ahmed Shehzad (55 off 62 balls) and Mohammad Hafeez (86 off 89) but patience won the day.
The slide began at 111 and, by the time Daniel Vettori had Shahid Afridi caught at deep cover for 11 to make it 187 for four in the 33rd over, the result seemed inevitable.
Vettori's miserly contribution of one for 41, including 31 dot balls, was the vital bowling performance. He was the most economical bowler, with Trent Boult the only other to go under five-an-over.
Complementing Vettori's parsimony, Nathan McCullum teased out a couple of deep mid-wicket catches and Adam Milne's control on a small ground, including his yorker, got a decent workout.
Earlier, Williamson was Michelangelo with a bat rather than a brush.
His sixth ODI century added further brushstrokes to a Sistine Chapel summer.
Children in the stands aped the strokes to their parents.
Even when Williamson advanced down the wicket, he held the shape of his shots rather than taking the easier route of clearing the front leg and blasting towards the Hawke Bay horizon.
Like the best subcontinental batsmen, he seldom overhits; it's more about the timing.
Williamson is now ranked the sixth best ODI batsman, behind AB de Villiers, Hashim Amla, Virat Kohli, Kumar Sangakkara and Tillakaratne Dilshan, but it's understandable why captain Brendon McCullum says he wouldn't swap him for anyone.
A vociferous crowd rose in unison as Williamson departed, just as they did for Taylor at innings' end. They knew they had witnessed quality.
Williamson received valuable support from Martin Guptill, with 76 from 88 balls, in a confidence-boosting innings ahead of the World Cup. Their second-wicket partnership was worth 128.
Grant Elliott also played another handy cameo with 28 from 21 balls, helping add 72 for the fourth wicket in 46 balls with Taylor.
Pakistan were faced with formidable bowling conditions but tended to drop too short.
They were punished through the short square boundaries.
Only Shahid Afridi with one for 57 and Mohammad Irfan (two for 52) conceded less than a run a ball. Bilawal Bhatti went for 93. Afridi's effort was diluted by Sarfraz Ahmed missing a couple of stumpings. Sharper work on Taylor's bails would have saved 77 runs.
New Zealand's win is their fourth series win in the last five, the only blemish being against South Africa earlier in the summer without Williamson or Taylor.
3 Things about this match
Two hundreds
It's the fifth time two New Zealanders have scored ODI centuries in the same innings.
100th 100
Taylor's century was the 100th scored by a New Zealander in an ODI.
Under fives
Boult (4.28) and Vettori (4.10) were the only bowlers to go at under five-runs-an-over.
Guptill rewards selectors' patience
Patience has proven a prudent policy from the New Zealand selectors with Martin Guptill.
The verdict comes after Guptill made 76 from 88 balls in last night's match against Pakistan in Napier.
It was the opener's best ODI innings this summer, adding to a steady 39 off 48 balls in Wellington. A summer ODI average which looked flaky at 19.82 with a strike rate of 65 two matches ago marches towards respectability at 25.62 with a strike rate of 71. It reflects the form he'd established at Ford Trophy level with the second-highest average of 69.50 in four matches over the Christmas holidays.
Coach Mike Hesson has played the situation brilliantly, saying he didn't want to create a "headmaster's office" culture. He never flinched as questions about Guptill's form became repetitive and eventually a source of public angst.
Hesson said it was sometimes difficult, as any cricketer knows, to translate practice in the nets into the pressure of a game.
The impact of Guptill's fielding is also important. He saves a stack of runs and places batsmen on the heels, rather than the balls, of their feet, especially within the 30m circle.
Guptill responded positively to Hesson's act of faith, even if he had to walk to the middle of McLean Park with Pearl Jam's Can't find a better man lyric blaring in his ears.
He was defensive to start, getting to 19 off 43 balls before accelerating as he judged the length better. His left elbow was high and he appeared less impulsive.
He waited until the ball was below his eyeline, perhaps a nod to the tutelage of New Zealand great Martin Crowe.
