USA boss Mike Tolkin was disappointed with errors against Japan but pleased overall with his side's World Cup performance.
The Eagles missed out on a win in the competition, coming bottom of Pool B which contained South Africa, Scotland, Japan and Samoa.
Despite that Tolkin was upbeat when addressing the media following his side's loss to Japan at Kingsholm on Sunday.
“It was pretty clear we made some simple errors and whenever we scored we allowed Japan straight back into the game. We had momentum and then let it slip at critical times which was disappointing today," Tolkin said.
“I think it has been the best we’ve ever performed [at a World Cup].
"We have been consistent in every game and showed moments of brilliance and periods of good play, unfortunately our game management and other areas let us down.”
Japan's stunning win over South Africa and other strong performances from Tier Two nations are a major step forward for the sport as a whole, Tolkin believes, with more shocks possibly on the way in 2019.
“I think it’s certainly a big stepping stone; the margins of victory have been far lower than previous tournaments," he added.
"There haven’t been the massive blowouts in certain games and every game has been tough, so I think it will be interesting to see what happens in 2019 with Tier Two teams."