Number eight David Denton summed up the emotion best as Scotland fell agonisingly short of a first World Cup semi-final appearance since 1991 on Sunday.

Fly half Bernard Foley displayed nerves of steel as his controversial last minute penalty kick gave Australia a 35-34 triumph over the Scots in a pulsating clash at Twickenham.

Tries from Tommy Seymour, Peter Horne and Mark Bennett - plus 19 points from scrum half Greg Laidlaw - looked to have given head coach Vern Cotter's men a shock win as the thrilling quarter-final entered its final minutes.

But the Wallabies were given a lifeline when referee Craig Joubert called a deliberate offside when replays seemed to indicate the ball had come off a Wallaby player.

Foley made no mistake to set up an all southern hemisphere semi-final line-up after Argentina's 43-20 win over Ireland in Cardiff.

"It's lucky you have caught me an hour after the game (laughs), this is the toughest loss of my career for sure," said Denton.

"It's devastating to play the way we did and not come away with the win.

"I went and met my family and girlfriend after and I think we could have filled a bath with all the tears."

"The ball is oval sadly and it bounces in different directions. A bounce of the ball has changed the next four years of our lives.

"It's unbelievable, it is literally centimetres that have dictated what's happened and it's devastating.

"My family thought we didn't have a cat in hell's chance, inside though we knew we had played OK and it was the time for us to do well. Saying that, Australia were due a bad day too."

Meanwhile, Wales boss Warren Gatland admitted his players were devastated after their defeat to South Africa in the World Cup quarter-finals at Twickenham.

Gatland's side led 19-18 with five minutes left at Twickenham but Springboks captain Fourie du Preez dived over to seal a dramatic 23-19 victory.

It means Wales' World Cup dream is over while South Africa go through to the semi-finals to face either France or reigning champions New Zealand.

"Sum up my emotions? That's a dumb question. How do you think we are? We're absolutely gutted," Gatland said.

"We're proud of the performance, but if you ask about the emotions that's not something I want to talk about.

"The guys put their bodies on the line, gave everything. That's all we can ask of them, but we weren't good enough to hold on for 80 minutes.

"Credit to South Africa, they stayed in the game, but we're very disappointed."