WARREN Gatland is sweating over yet more injuries ahead of Wales' quarter final after Jamie Roberts and Liam Williams left the field injured in their 15-8 defeat to Australia.

Having already lost Rhys Webb, Leigh Halfpenny, Scott Williams and Jonathan Davies in the backline - Gatland will be hoping the influential pair pull through to face the Springboks on Saturday.

Roberts' injury seemed less of a concern to the hard-nosed Kiwi, but Liam Williams is thought to have suffered a recurrence of the foot injury that kept him out of the World Cup warm-up matches.

Gatland said: "I think the guys are a bit battered and bruised.

"That's what test rugby is all about these days and we know we've got a seven day turnaround which will give us time to recover."

Wales' defence was heroic, but their attack lacked a cutting edge.

Three times they were held up over the line and with George North filling in at 13, the ball rarely made its way outside his channel.

When asked whether Australia's defence won them the game or if Wales' attack lost it for them, Gatland said: "I thought it was courageous defence by Australia really throwing their bodies on the line.

"We were over the line three times held up, so for me it's really fine margins.

"If Dan Biggar kicks the penalty just before half time then it's 9-9 and we're then 12-9 down instead of 12-6 in which case you take the three points.

"So it was a really tight, close test match and I don't think there was much between the two teams.

"I think defensively they didn't put us under a huge amount of pressure with their attack and I thought there were times where we played some good rugby."

The head coach proved once again he has one of - if not the most - shrewd minds in the sport with his choke tackle tactic to blunt the usually razor-sharp Australian attack.

He said: "It was a strategy for today.

"We'd worked during the week on holding them up, but not just that area.

"We had to look at what was effective in slowing the Australian ball down because we know what a threat they are as an attacking side.

"If we can slow that ball down, and we're using different techniques for doing that, then we can realign defensively and it negates their attacking threat.

"I thought we did that extremely well."

Another pleasing aspect of the Welsh performance for Gatland was the reversal in fortunes of the scrum.

He made two changes - bringing in Paul James for Gethin Jenkins and Samson Lee for Tomas Francis - and the scrum held firm against a Mario Ledesma-inspired Wallaby scrum that has somehow become one of the best in the world.

But Wales' perceived dominance in the scrum, with the Australian pack able to smell the whitewash of their own try line, was not spotted by Craig Joubert.

The referee allowed a number of scrums to crumple as Australia's sin bin time ticked away and when pressed on the South African's performance, Gatland said: "I can't really comment about the referees otherwise I'll get a huge fine, but I'll try and get my feet back through World Rugby on the referees.

"There's probably one scrum where we've picked up and gone on the blind side and had we kept it in there was a good chance we could've capitalised on that because we were going forward.

"In fairness to Australia, they've done a great job defending that.

"We created our opportunities, we just haven't finished them off.

"That's something we need to be critical of and look at ourselves."

During that time, Wallabies skipper Stephen Moore was vocal with the referee, and Gatland gave kudos to the hooker for the way he went about his business.

He said: "I think he was quite comfortable talking to the referee as much as he could to wind the clock down as much as he could.

"He as pretty smart in the way he did that.

"Sometimes it's easy if you're a captain as a hooker because you're right there in front of the referee and it gives you a bit of a licence to communicate with him a little bit more.

"But I think I'll need to go back and have a look at that, but we were conscious that with Will Genia off the clock was winding down at scrum time."

The players will have tomorrow off and will take part in recovery sessions on Monday before going head-on into a week of training culminating in a sudden death tie with South Africa.

There will be no hangover for Gatland's men.

An Australian win is proving as elusive as an eel in olive oil for Wales - this their 11th defeat on the bounce - but Warren Gatland's men know how to beat the South Africans. 

He said: ""What's pleasing for me is - and the boys have talked about it in the changing rooms - their mind has already turned to next week.

"They want to beat South Africa and we did that at home 12 months ago and we threw it away twice over there when we were ahead by 17 points.

"We've learned a huge amount from that, but the focus will be purely on beating South Africa.

"We've got to match their physicality up front, their one-up runners off 9, compete at the set piece and then you've got a chance.

"It just shows what character they've got.

"Obviously they haven't had a great 12 months as a side, but when their backs have been against the wall, they've shown the character they have got.

"They've got some young players who are pretty exciting as well."