Legend Phil Bennett believes there will be "no limit" to Wales' future success if the Grand Slam winners can beat Australia in June.
Warren Gatland's side take on the Wallabies in three tour Tests.
Wales' 1976 and 1978 Grand Slam fly-half says coaches Warren Gatland and his "genius" sidekick Shaun Edwards can drive them on to greater glory.
"If we can beat those, I think there's no limit to what the... squad can achieve," Bennett told Scrum V.
"I think they've [Gatland and Edwards] brought this winning element into the Welsh side and now, they're the fittest side in world rugby, I believe.
"So if we can get those fitness levels going, [with] the strength in depth we have at the moment - we need to go down to Australia and put our hand up and say: 'hey, we're not frightened of you any more' and we need to take those kinds of sides on.
"If we can beat those, I think there's no limit to what this side - the squad - can achieve, because we are a squad, not a team; a huge squad with great men backing us up there."
In the wake of Wales' Slam-sealing 16-9 win over France at the Millennium Stadium Gatland set his sights on beating Australia, New Zealand and South Africa.
But they may have to face the Wallabies without skipper Sam Warburton following the shoulder injury that forced him off against France.
Wallabies wing legend David Campese said Wales' it was "about time" Wales won a trophy.
He says Wales' fourth-place finish at the 2011 World Cup was ultimately "disapppointing" after their earlier performances at the tournament.
Campese also felt Wales were below par in their November defeat by Australia that signalled the end of Shane Williams' Test career, but that during the Six Nations showed "under pressure that they can play some good rugby".
And he expects the worldwide reaction in the game to accept that Wales could challenge the traditional world order that has been largely dominated by the southern hemisphere powers.
"From last year's World Cup, they've demonstrated that they've got a side that can go further in the competition - it was disappointing the way they finished the World Cup and against Australia last November.
"But I suppose now that they've won the Six Nations and the Grand Slam and all that - I think a lot of people around the world will be a bit worried."
Wales' try-scorer against France, 6ft 6in wing Alex Cuthbert impressed the Australian.
But he warned the 21-year-old Cardiff Blue that his efforts during the tournament will ensure greater scrutiny by opponents in future.
"I think now people are going to be watching him a lot closer," said Campese.