Dan Biggar is in the final swansong of a glorious international career but the veteran fly-half said on Friday he is not yet ready to hang up his Wales boots.

The 33-year-old returns to head coach Warren Gatland's starting XV for Saturday's World Cup quarter-final against Argentina in Marseille after suffering a chest injury during Wales's record 40-6 thrashing of Australia in the pool stages three weeks ago.

He was an unused replacement in Wales's 43-19 pool stage win over Georgia last week after he was called up at short notice when Gareth Anscombe pulled his groin in the warm-up, resulting in young fly-half Sam Costelow being promoted from the bench to play the entire 80 minutes.

Biggar has already announced that he will retire from international duty once the World Cup is over, but he is desperate to prolong his Wales career by an extra couple of weeks.

"I really don't want this to be my last day as a rugby player for Wales, I want it to be another two weeks and hopefully that will be the case," said Biggar, who is not the only Wales veteran set to retire after the tournament.

A third of Gatland's original 33-man squad are aged over 30.

"For us in that boat who are definitely finishing -- it's not an if, it will be finishing after the World Cup -- there is a little bit of extra pressure.

"But it's also a huge motivation, it's something that I definitely don't want my last day as a Welsh rugby player to be losing a quarter-final."

- 'Absolute madness' -

The turnaround in Wales's fortunes since a dismal fifth-placed finish in the Six Nations earlier this year has been remarkable.

Since Gatland returned to the helm in January, Wales have become a completely different proposition to the Wayne Pivac years and they start Saturday's match as favourites to beat the Pumas.

"It's funny how things and time change," said Biggar.

"Probably three, four, five months ago, if somebody had said we were going to win our pool and be in a really strong position to get to a semi-final, people would have said you were talking absolute madness.

"It just shows how much confidence we've had, how much belief we've had in the group as the weeks have gone by and the more time we've spent together.

"This is the reason why you play rugby really: big occasions, quarter-final of a World Cup."

Although Wales have been one of the revelations of the World Cup, dominating a tricky pool featuring Australia and Fiji, as well as a Georgia team that beat them for the first time less than a year ago, Biggar admitted he was relieved to have avoided the competition's favourites in the last eight.

With the world's top four teams -- number one Ireland, hosts France, reigning champions South Africa and three-time winners New Zealand -- all on the same side of the draw, Wales have a clear opportunity to reach a third semi-final in the last four editions. 

"I think all of us are really glad we're on this side of the draw for a few reasons," he said.

"The prize at the end of it is exactly why we want to be involved in weeks like this."

bc/pi