The Wallabies’ World Cup hopes could rest on the medical reports of injured trio David Pocock, Israel Folau and Scott Sio – all of whom are in doubt for next week’s semi-final against Argentina.

While they escaped with an extraordinary one-point win over world No.9 Scotland at Twickenham on Sunday (Monday AEDT), it was clear just how much the Wallabies missed influential pair Pocock and Folau.

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Pocock, who missed the 35-34 quarter-final victory with a calf injury, has blossomed in his newly-adopted role of No.8 and remains world class at the breakdown, leading the tournament in turnovers in that area with 10.

Noting his absence, Scotland deployed two traditional No.7s and made it their mission to control the breakdown – and did so, winning five turnovers to Australia’s three in an area the Wallabies had dominated through the pool stages.

Pocock’s replacement, Ben McCalman, finished with five tackles and no turnovers, but proved his value with ball in hand and crossed the gainline six times in a gutsy 80-minute display.

However, whether Australia can win the World Cup – or even beat Argentina next Sunday (Monday AEDT) – is another matter entirely and coach Michael Cheika will be anxiously assessing Pocock’s improvements in overcoming the calf complaint suffered last weekend.

“The less injuries you have the better, no doubt,” captain Stephen Moore said.

“We’ve already faced some injuries this tournament.

“A guy like David, he’s a very special player.

“He brings so much to the game that you’re certainly going to miss that (when he’s not playing). But the guys that played tonight did a fantastic job.”

Kurtley Beale, who was promoted from the bench to cover for Folau (ankle), looked sharp against Scotland – and a constant threat when running the ball.

“I thought Kurtley Beale was fantastic,” Moore added.

“He was one of our best out there tonight. He was just so consistent across the 80 minutes.

“That’s what you want – when someone misses out like Izzy did, that someone steps in and does the job.”

More importantly, Beale has been a huge asset to the Wallabies as an X-factor off the bench – and his replacement in that role, the enigmatic Quade Cooper, wasn’t given an opportunity by Cheika to enter the game.

Sio, meanwhile, endured a difficult afternoon and conceded several penalties for collapsing the scrum before leaving the match mid-way through the second half with an elbow injury.

However his involvement at the World Cup has been outstanding and he’s been central to the Wallabies’ scrum shedding its “fragile” tag.

He was seen late in the match with his right arm in a sling and will have further assessment on Monday.

– AAP