WARREN Gatland insists the race for the right to wear the Wales No 10 shirt against Australia later this month is wide open between Dan Biggar and Rhys Priestland.

With James Hook out of the equation – because he doesn’t have a full release clause in his Perpignan contract for the Wallabies clash – it will be a straight shoot-out between the two for one of the most coveted jerseys of all.

Biggar is Wales’ outside-half for tomorrow’s clash with Argentina in Cardiff after Gatland went with Priestland last weekend.

Scarlets man Priestland was disappointing in the 24-15 defeat to South Africa in his return to the Test arena for the first time in a year, recovering from a serious and recurring Achilles injury.

Ospreys fly-half Biggar missed out completely for the Boks clash and it is his rival who is not even among the replacement this time for the Pumas showdown.

Gatland also revealed yesterday Hook, Biggar’s fly-half back up tomorrow, is likely to make his first start for Wales at outside-half in two years next Friday night when Tonga are the visitors.

Ex-Ospreys man Hook has been seriously out of favour with the Wales management in his favoured position and has had to make do as a bit-part player as a replacement in the 2012 Grand Slam and this year’s successful Six Nations defence.

His last Test start at No 10 was the 21-18 defeat to Australia in the third/fourth placed play-off showdown in the 2011 World Cup at Auckland’s Eden Park.

Gatland was asked yesterday if the fly-half jersey was up for grabs against the Wallabies in their last game of the autumn on November 30, Wales having suffered eight straight defeats against the Aussies which stretches back to November 2009.

He replied, “yes,” before adding that tomorrow is a huge opportunity for Biggar to stake his claim.

“Dan’s done really well last term in the Six Nations and he's trained well this week,” Gatland said.

“We were pleased with the way Rhys trained. There were probably a few aspects of his game that he'll take from last weekend, having not played at that level for a while.

“So, yes, it's a really big chance for Dan. And, hopefully, James Hook will get a chance next week, even though he won't be available for the Australia game, which is unfortunate. “Probably with those two we'll make a decision afterwards who we'll pick at ten for Australia.”

Hook, 28, is unavailable for the Wallabies game because it falls outside the International Rugby Board Test window and he doesn’t have a clause in his contract with Perpignan releasing him for it.

Wales go into tomorrow’s encounter with Argentina, shockingly, without a victory in their autumn internationals since beating the Pumas 33-16 in 2009.

Gatland makes three other changes to the team which lost to South Africa last Saturday.

He awards a new cap to 6ft 3in and 15st 10lb Cardiff Blues centre Cory Allen, 20, who replaces Jonathan Davies, out for months with a serious pectoral injury.

Scarlets tighthead Rhodri Jones, 21, wins his third cap for long-term absentee Adam Jones (calf), while openside Justin Tipuric comes into the back row, captain Sam Warburton on the blindside for Dan Lydiate out with an ankle injury.

Wales: L Halfpenny, G North, C Allen, S Williams, Liam Williams, D Biggar, M Phillips, G Jenkins, R Hibbard, Rhodri Jones, B Davies, A W Jones, S Warburton (capt), J Tipuric, T Faletau.

Replacements: K Owens, P James, S Lee, L Charteris, Ryan Jones, Lloyd Williams, J Hook, A Beck.