Justin Tipuric says it is "time to act" when Wales faces a World Cup clash against Australia that could shape their fate in the tournament.
Wales' victory against Wallabies will set them in the red-hot favorites to win Pool D and secure a likely quarter-final clash with France or Argentina.
But if Australia beats Wales for the 14th time in their last 15 matches, it could send Tipuric and the company attacking in the eighth final clash against England.
"There are no bones about it, and both teams want to try to break through and end the relationship in the group," said Wales' creator Tipuric.
"There have been some tough results in the past but it was nice to win last fall against them (Australia).
"I think they will be happy to get it back from us and we want to make sure we get another win.
"Before we got here, you knew this was going to be great. We're here now, it's time to act, really. "
Wells in World Cup history claimed only one victory against Australia, New Zealand or South Africa – and that was 32 years ago in the third-place playoffs when they defeated Wallabies.
And their overall record under coach Warren Gatland shows just seven wins from 41 attempts at the hands of the three heavy rivals in the Southern Hemisphere.
Wells broke a string of 13 tests at the hands of Australia last November, with Tipuric set to be among the few survivors of that 9-6 success that ended at Tokyo Stadium on Sunday.
Asked if there was a mental block before that victory, Tipuric added: "It's hard to say.
"Those games are so tight, there are maybe … people would expect there is a bit of a mental block, I don't know.
"At the end of the last game we probably left about 15 points there, so it made the score look much closer than it really was."
If Wales is to triumph, then Tipuric's battle for the breakup with Australia's respected double act Michael Hooper and David Pocock will be crucial.
67-year-old Tipuric has hit both players on several previous occasions, and he knows exactly what is coming.
"They are absolutely seven world-class," he said. "When you play against world-class mirrors, you always know you're going to have a tough game.
"Those two are constantly there with the best in the world. You know what kind of game you play.
"Pozzott is one of the best players in the world through the ball defensively – and Michael is more than seven offensive tackles and probably has a bit more than a rugby brain to be in the right place at the right time.
"You'd better play the best players in the world and you would be challenged, rather than a back-up guy who wasn't that good. You want to play against the best and know against the two you have to be in shape.
"I wouldn't say Sunday is such a cup final, but it's an important match for us at this World Cup.
"Momentum is an important part of that. If you continue to build and perform well, you will fly and be hard to win. "