Root’s blistering 79 from 56 deliveries, aided by an unbeaten knock of 65 from Jonathan Trott, saw England cruise to their target of 270 after dismissing the home side.
Captain Cook was effusive in his praise of the Yorkshireman Root, who became the first England player to pass 30 in his first six ODI innings.
“He’s got the makings of a very good player,” Cook said of the 22-year old, “He keeps his feet on the ground, works very hard and has the right temperament for international cricket.”
Cook, who made 78 at the top of the England innings, added: “He’s adapted very well to new roles.
“He opens the batting for Yorkshire in four-day cricket, he’s batting at six for us in Test matches and batting in the crucial position of four in one-day matches. He’s done incredibly well.”
The platform for England’s triumph was laid by the bowling attack, who dismissed the New Zealanders for 269, with new record wicket-taker James Anderson picking up 5-34.
“You know Jimmy is going to bowl pretty well pretty much every time,” said Cook. “It was a pretty strong wind and he bowled all his overs into that wind, so it was a great effort.”