Wales took a huge step towards topping Pool D at the Rugby World Cup with a nail-biting 29-25 win over a fast-finishing over Australia in Tokyo.

First-half tries from Hadleigh Parks and the outstanding Gareth Davies made the Wallabies pay for a slow start and set up a result which should see Wales avoid a quarter-final date with England.

Warren Gatland's men did have their 15-point half-time lead trimmed to one during the second period but held firm with help from Rhys Patchell's vital third three-pointer.

The Scarlets fly-half only came on after Dan Biggar was forced off due to concussion, the lone setback for Wales on Alun Wyn Jones' 130th cap, a national record.

Wales made a fast start in their tournament-opening win over Georgia and did the same on Sunday as a Biggar drop goal punished Australia's turnover from the kick-off.

Fly-half Biggar was involved again for the first try of the match when Parkes rose high to claim an intelligent kick and extend the margin to 10 points in almost as many minutes.

Australia's nerves eventually started to settle and the recalled Adam Ashley-Cooper got his team on the board by meeting Bernard Foley's cross-field kick.

Foley missed the conversion but made amends with a three-pointer prior to the half-hour mark.

The influential Biggar failed a head injury assessment following a try-saving tackle on Samu Kerevi, yet his absence did nothing to hinder Wales.

His replacement, Patchell, nailed a pair of penalties and extended the lead to 23-8 at half-time after Davies made a second interception, this time from Will Genia, and raced clean through, albeit from a seemingly offside position.

Patchell's successful drop goal in the early stages of the second half prompted Michael Cheika to swap Foley for Matt Toomua and it was the latter's break that ended with Dane Haylett-Petty diving over on the right.

Australia grabbed the momentum and reduced the deficit to four points 20 minutes from the end, Michael Hooper squirming over following a sustained period of pressure.

Toomua made both conversions and then put the Wallabies within one point with a successful penalty, but Patchell responded to give a tiring Wales breathing space in the closing moments.

Wales shed Wallabies hoodoo

Gatland's men beat the Wallabies 9-6 in Cardiff in November 2018 but had lost the past five World Cup meetings between the nations.

Ending that run and avenging the 15-6 pool match defeat to Australia four years ago could provide the impetus for a run deep into the tournament.

Cheika's big call backfires

Australia coach Cheika turned to experience to combat Wales, making four changes to the backline that helped secure a 39-21 win over Fiji.

He might be regretting that decision. Foley and Genia were drafted into the halves and, for experienced players accustomed to this stage, were prone to basic errors that invited pressure.

What's next?

The Wallabies have work to do ahead of Saturday's game against a Uruguay side boosted by a surprise win over Fiji, who are Wales' next opponents on October 9.