TWICKENHAM -- You can call it guts, determination, spirit or fight, but to an Australian, the Wallabies' incredible 15-6 win over Wales falls under one simple category: ticker.

Incredible not because of free-flowing attack or the crisp execution of the game's most basic skills, but incredible because of the way in which they defended their line when down to 13 men.

Saturday evening's triumph was all about ticker -- and this Wallabies team appear to have it by the bucket load.

From the outset, it was clear their second trip to Twickenham of this Rugby World Cup would in no way resemble their first -- a relatively one-sided victory over England last weekend -- as Wales started the stronger and came within inches of scoring inside the opening two minutes.

The Welsh had come to Twickenham with a clear game plan to flood the breakdown and test the Wallabies under the high ball. A cunning Warren Gatland had instructed his side to use the choke tackle too, a ploy from which they enjoyed great success. The Wallabies were entering tackles too high, and Wales were reaping the rewards.

Eventually Australia found some sort of rhythm, largely on the back of their now world-class scrum, while Scott Fardy and David Pocock began to win the favour of referee Craig Joubert at the breakdown. Bernard Foley booted the Wallabies out to a 9-6 lead before Dan Biggar was given the chance to level the scores just before the break. He missed. And it looked to be crucial.

Seventeen minutes after the resumption it shouldn't have been. First Will Genia was given his marching orders after opposite number Gareth Davies took a quick tap and caught him offside. Joubert had no option but to send the Wallabies No.9 to the sin-bin such has been the consistency of that ruling this season.

A couple of minutes later Genia was joined by Dean Mumm, the lock infringing at the lineout after Joubert had issued a general warning to Wallabies skipper Stephen Moore only moments before.

With Australia down to 13 men for seven minutes, Wales' opportunity had arrived.

Australia refused to be beaten Paul Gilham/Getty Images

Time and time again they came at Australia as skipper Sam Warburton opted to kick for the corner. The Wallabies held out.

Taulupe Faletau bullocked his way over from close range and the decision went up to the TMO. No try. Still the Wallabies held out.

Wales then tried their luck from a five-metre scrum. The Wallabies pack -- down to seven men -- still held out.

Outside-centre George North then flew down the right wing where he was confronted by Foley who cut the Welshman down before Ben McCalman scrambled back and finished the job. Still the Wallabies held out. Wales had been guilty of white line fever in the early part of their two-man advantage but that wasn't the case with North's effort.

The final act of this amazing defensive sequence came when Adam Ashley-Cooper made a fine one-on-one tackle before winning a penalty for holding on. The Wallabies had held out. Wales will likely look back at the tape and wonder how they didn't score. Many Wallabies players might just, too.

One thing Michael Cheika's troops won't be wondering about is the kind of commitment and attitude that exists within their team.

Cheika, as has been his custom throughout this tour, did his best to talk down the Wallabies' show of defensive fortitude at the post-match presser before eventually admitting he was "very proud" of the effort.

Wales coach Warren Gatland was far more forthcoming, describing it as "courageous" and "heroic". The New Zealander has now lost 11 straight matches against the Wallabies as the coach of Wales. What he might give for a little more ticker.