Shane Watson justified the faith of captain Ricky Ponting on Friday with an innings which shattered New Zealand's hopes of containing the world champions in their final World Cup Super Eights match.

Returning to the side after yet another injury break, Watson gave as good an exhibition of clean hitting as anything seen in the tournament so far.

Sweeping the ball off his legs and hitting the ball powerfully on the drive he struck four fours and four sixes in his 65 not out from 32 balls.

Thanks to the powerful all-rounder's efforts, Australia added 66 in the final five overs to reach an imposing 348 for six.

With the ball, Watson bowled James Franklin for six in his first over and finished with one for 20 from his five overs as the Kiwis collapsed to 133 all out.

Watson missed the 2003 World Cup with a back injury and the last Ashes series with a hamstring complaint. He then strained a calf muscle against Bangladesh and did not play in Australia's last three games.

On Friday, Watson showed why he is so important to the balance of the team with bat, ball and in the field.

"Shane Watson is a very, very good and very, very talented cricketer, someone that works extremely hard at his game," Ponting, whose side have won all nine of their matches at the tournament, told a post-match news conference.

"He hasn't had a great run with injuries but if you look at his form in the one-day team over the last couple of years he has hardly put a foot wrong.

"He's opened the batting and his bowling in the one-day game over the last couple of years has been great.

"The way he struck the ball today was very pleasing for everyone."

Watson's assault followed 66 by Ponting and 103 from 100 balls from opener and man-of-the-match Matthew Hayden, his third century of the tournament.

"I think we've worked very hard throughout this summer in our one-day game and all elements of our game," Hayden said.

"So I guess it's no surprise we're here at the World Cup at the height of our game having played a lot of cricket.

"We're looking forward now to the next two games. All that we have achieved means nothing if we don't go all the way."