Just hours after engineering his side's shutout of New Zealand to win the Oceania U20 championship, the celebrations had stopped for coach Jason Gilmore.
Gilmore and his staff had to cull four players from the squad that had emerged unbeaten from the Oceania campaign and become the first side other than New Zealand to win the title.
"It's a good thing that it's so hard to make those decisions but they're definitely hard decisions to make," said Gilmore, who met with his coaching staff on the Gold Coast on Saturday night to finalise the 28-man squad to head to Argentina in June.
Players were informed of the decision on Sunday, with Rugby Australia submitting the squad list to World Rugby, who will release all teams on May 7.
The depth in some positions - the backrow in particular - means some outstanding players will be left behind and left Gilmore and his staff with an unenviable selection task.Three camps ahead of the Oceania tournament and a fortnight in camp on the Gold Coast have the Junior Wallabies in good shape ahead of the world championships.But Gilmore knows his side cannot afford to get complacent ahead of a challenging pool B in Argentina that includes England, Ireland and Italy.
"I think for the boys, (the Oceania championship win) is just good reward for the effort they're putting in and confidence in the systems we've got in place," Gilmore said.
"But we can't get ahead of ourselves either.
"World Cup rugby is completely different and in 2016 we beat New Zealand here as well and lost the first game to Scotland over there.
"So we've got to make sure that we keep grounded and keep working hard and keep enjoying what we're doing."
Captain Fraser McReight said the result was important for Australia."I don't think anyone has done that for a whole and that's huge for Australian rugby because of what's happening at the moment," McReight said.
"It shows that Australian rugby is awesome and success is going to come in the future.
"It is important. There were probably comments around this team in the lead-up that we weren't up to scratch but we were able to back up our talent on the ground and that's just unreal."
Gilmore agreed it was exciting for the sport in Australia.
"There's a lot of good things happening through this space and at under age and club rugby and NRC," he said.
" I think a lot of those good stories get overlooked at times with results at the top level but these guys are the ones we want in the next senior World Cup.
"Winning's important for them and we're developing some good players."