USA head coach Mike Tolkin called on his team to improve their discipline for their next match against Scotland after losing to Samoa 25-16.
The Eagles lost out in the battle at the breakdown as Tusi Pisi punished them with points off the tee, culminating in a nine-point margin on the scoreboard.
Tolkin focused on the areas he wants to see the Eagles work on after a rusty start to their World Cup campaign.
"We need more discipline. We're not going to get the penalty count that we had today. Our scrum held up well but our lineout, which has been a strength, wasn't operating as efficently and needs to be straightened out. We also need some more continuity, capitalising off those line breaks that we made but didn't make the most of today," Tolkin said.
"It's one game at a time and the try for Chris [Wyles] was outstanding. The positive is that those chances are occuring, but we just have to make the most of them."
Tolkin added that the USA played into Samoa's hands through their penalty count and loose kicking, while regretting the fact that the side missed out on a losing bonus point.
"One of the things when playing the Pacific Island teams is you don't want to give possession away and in the first-half espeically we did that. Penalties were a part of that and really put us on the back foot throughout the game," he added.
"With the Pool being wide open from Saturday, those bonus points are important so it was disappointing to not take something out of it at least."
Japan's impactful win was a proud moment according to Tolkin not just for Eddie Jones and his men, but all the Tier Two nations.
"It was a fantastic, historic win for them," he said.
"In our circles, we play them quite a bit almost once a year and it's always tight. To show that teams are on the rise at our level is great for the game. Overall I think it's fantastic for the fans and for the sport."
Fly-half AJ MacGinty was the standout performer for the USA in only his sixth cap, with USA captain Chris Wyles, who was set up for his try by the fly-half's break, underlined how important he is becoming for the team.
"He's playing really well for us. He's pretty new onto the scene and international rugby, but his game management is huge for us with this kicking abilities. He really attacked the line and made some breaks for us today. We need to get on the same page as him, but he's running the ship really well and growing in every game."
Wyles also discussed the combined huddle between the American and Samoan players after the final whistle in Brighton.
"It's something the Samoans like to do after games and it's a nice moment. It shows there's a lot of camarderie in the rugby world."