LONDON (AP) — In describing Australia's success in shutting out Wales while playing with 13 men, the Wales captain and coach didn't hold back. They used words such as "courageous" and "heroic."

Asked for his assessment, Wallabies skipper Stephen Moore said: "Guys just did their job."

The veteran hooker was typically blunt after Australia prevailed 15-6 in their Pool A decider at the Rugby World Cup on Saturday, as if there was nothing extraordinary about his undermanned side withstanding wave upon wave of Welsh attacks, backed by a partisan crowd of 80,863 at Twickenham.

"It's not complicated," Moore said. "We just try to keep it simple, just working hard for each other."

But the Wallabies worked triple overtime while teammates Will Genia and Dean Mumm were in the sin-bin, to set up a quarterfinal back at Twickenham next weekend against No. 9-ranked Scotland, and leave Wales to face two-time world champion South Africa.

Flyhalf Bernard Foley was the main contributor to the scoreboard for the second successive week, landing five goals from six attempts for all of Australia's points. He scored 28 in the 33-13 win over England the previous weekend that ended the host team's hopes of advancing.

His opposite number Dan Biggar, who piloted the Welsh comeback in a 28-25 win over England two weeks ago, kicked all of his side's points.

The mantra under coach Michael Cheika's year-long tenure at the Wallabies has been about building up belief. There was plenty of belief on display in defense, helping to overcome flaws in attack and discipline and the immense pressure from a Welsh team desperate to end a 10-match, seven-year losing streak to the Wallabies, many of them heart-breakers.

Australia led 12-6 when scrumhalf Genia was sent off for impeding Gareth Davies' quick penalty tap in the 57th minute, and when lock Mumm followed him off for an infringement in the lineout two minutes later.

Desperate tacklers launched themselves at Welsh ball-runners, keeping out attacks close to the ruck and out wide. Australia's pack held firm despite the numeric disadvantage, forcing Wales to use a series of penalties on lineouts instead of scrums.

Two Welsh players crossed the tryline in the period when they had a two-man advantage but were held up, including big outside back George North who charged into the corner but was bear-hugged by replacement backrower Ben McCalman.

"You don't magically find that on the weekend," Moore said. "It's something that we've worked hard on."

That's something Wales coach Warren Gatland knows. He called Justin Tupuric into the backrow and moved captain Sam Warburton to the blindside flank to focus on strangling Australia's supply of quick ball, and the Welsh achieved that with their choke tackle technique and commitment at the breakdown.

Gatland praised the courage and quality of the Australian defense, and the performance of his own team, which he didn't expect to dwell too long on the loss.

"What was pleasing for me was in the changing room the guys are already focused on next week," he said. "The focus will purely be winning that quarterfinal."

Warburton said he had no regrets about pushing for tries when there were penalty goals on offer.

"We felt we needed a try to beat Australia. We were six points behind and two penalties would have brought us to a draw," he said. With a two-man advantage, "Any country would have backed themselves to go over."

But after absorbing all the pressure, making more than double the number of tackles than the Welsh, defending their line for long periods, the Australians added a late penalty goal to extend the lead and missed late chances for a try when Israel Folau slipped over on a counter-attack, and Wales winger Alex Cuthbert was yellow-carded for a deliberate knock-on that stopped a potential try-scoring movement.

"You have to give Australia a lot of credit," Warburton said. "I am happy, though. It was a tryless performance against one of the best attacking teams in the world."

Cheika said he was proud of the commitment his Wallabies showed, but expected improvement next weekend against the Scots, who have beaten the Wallabies twice in recent years.

The Australians were missing suspended vice-captain Michael Hooper's presence at the breakdown, but his replacement Sean McMahon made some bone-jarring tackles and could get another match next weekend if David Pocock doesn't overcome a calf muscle injury that forced him off the field. Folau was troubled again by a left ankle problem, and could be in doubt for the quarterfinals.