Australian U20s coach Simon Cron heaped praise on Samoa and the impact of his bench after escaping with a 33-26 win last night.
Cron left captain Reece Hewat, Jordan Uelese, Shambeckler Vui and Sione Tuipulotu on his bench and the players in their places failed to step up - with the exception of Rob Valetini.
Changes were made either side of half-time and bringing that quartet on proved to be a turning point.
"I think we probably played our game for a small period of time in that," Cron said.
"Samoa were extremely good.
"They came, they wanted it - they really wanted that game and they fought to the bitter end.
"We had a few guys out there playing their first game and I made the decision at the 35 minute mark that a few of them were probably in their own boat and not playing as a team.
"So I tried to help our cohesion by bringing on a couple guys.
"Then we brought Reece on just after half time to steer the ship."
Cron is a hard marker and wasn't particularly pleased with his team's performance but said they would be far better for the run.
"I'm happier now than if we had lost, naturally, but I'm process driven, not outcome driven so for us as a team part of our evolution is to understand the processes themselves - and they know that," he said.
"But also, these kids are 19 - some of them are 18 - so this game is really important in the evolution of their rugby brains.
"Being able to prepare for games properly and be ready for every single game."The one positive for us out of this game - apart from Samoa being tough, strong and brilliant - it's that these guys will now be more intelligent when it comes to their rugby brains."
Attention now shifts to Friday morning (AEST) and the blockbuster clash with England.
They beat Samoa 74-17 in their opener so that form line indicates the Aussies will need to be big improvers to stand a chance.
"We'll be better for the hit out that Samoa gave us and England will be a tough challenge," Cron said.
"Our boys are up for it."
The Australia U20s take on England on Friday morning, kicking off at 2:30am AEST LIVE on FOX SPORTS.