Tony Popovic's teams have always been built around defence.
So it should come as no surprise the new Socceroos boss got straight to work on his backline.
Predecessor Graham Arnold always favoured a back four, regardless of the fullback options available to him.
But a back three always appeared a good option - if someone was willing to test it.
Popovic has done just that, deploying Kye Rowles, Harry Souttar and Thomas Deng - who was replaced by Jason Geria at half-time - as his three central defenders, with Aziz Behich and Lewis Miller on the left and right flanks.
While there were some miscommunications and nervous moments - notably China's early goal from a mix-up between Deng and Souttar - the pros clearly outweighed the cons.
"I thought we were pretty positive, to be honest with you," Souttar told AAP.
"I've played a back three for a number of seasons a couple of years ago, so I've really enjoyed the position.
"I've played middle and to the right as well.
"I thought it worked well. Obviously the midfielders in front of us were really good and always showing for the ball, and then we always had options with the two No.10s that were playing.
"The more we play together, the more we train together, then the more fluid we're going to get, the better we're going to become."
Settling that defence will be crucial ahead of Tuesday's clash with group leaders Japan in Saitama, with Souttar conceding that Australia will have to get pretty much everything right.
After playing as the central member of the back three against China, Souttar is excited by its potential.
Athletic wing-back Miller ran tirelessly down the right all night against China, scoring a goal and winning fouls in dangerous positions with his run and dare.
"For our first game we kept the ball really well and we created a lot of chances and luckily enough in the second half we broke through," Miller told AAP.
"We're heading in the right direction and I think the formation, the players will adapt to, because not everyone plays overseas in their clubs or in the A-League plays in that formation.
"But I think with the right guidance, which I think we have now, we'll sort it out."
Goalkeeper Joe Gauci also backed the unfamiliar system, but expected it to function well after more training in Japan.
"The back three's something I've not played in front of before, so it was a bit of a different dynamic for me as a goalkeeper, in the build-up, supporting," Gauci said.
"We only got to work on it really briefly, but I felt quite comfortable behind it.
"There were some little moments in miscommunication, some missed passes and we might have been threatened in those moments.
"But apart from that, the boys that were in front of me were very solid."
