"In terms of fitness testing, he's as well as he has been for a good number of years," New Zealand coach Mike Hesson said yesterday.
"He's doing personal bests in a lot of strength and conditioning aspects, which is great. He's been training with our squad in Auckland since returning from the Caribbean Premier League [which finished on August 16]. He's travelling well."
The next part of the equation is to see Vettori back in match action. Hesson confirmed Vettori would be "involved in some capacity" in the warm-up games against the Scots and Irish at Lincoln and Hamilton on October 15 and 18 respectively.
Vettori will travel to Melbourne with a New Zealand squad for a training camp on October 7.
However Hesson baulked at suggestions that left arm spinner Vettori, who has taken 284 ODI wickets in 275 matches, is some sort of final piece in the spin puzzle for the cup squad. The selectors are very happy with the work of offspinner Nathan McCullum in the past year.
"But a player of Dan's experience and skill, he'll be in the mix for the next few months and play games and then we'll have to decide on the balance of the squad. Hopefully both are playing well."
The loss of part-time offspinner Kane Williamson, while his action is being modified, may mean a rethink in terms of the depth of spin the selectors will want in the group for the cup.
Vettori is likely to be in the group to the UAE for some of the ODIs before heading to the Big Bash League with the Brisbane Heat, which starts on December 21.
Then, if he is picked in the cup squad to be named early in January, he will line up in some of the seven ODIs against Sri Lanka which run through that month.
Vettori confirmed yesterday that he would play Big Bash only when New Zealand were playing their two tests against Sri Lanka straight after Christmas.
"To play the World Cup is my dream, so that's the priority," he said.
"Mike and Brendon [McCullum] have been positive and kept me in the loop around their planning and checked what I can achieve if I'm fit. Having that level of communication and support has helped motivation."