USA skipper Chris Wyles has revealed his disappointment in his team's discipline after they suffered defeat in their first Rugby World Cup match against Samoa.

The Eagles matched Samoa's for tries with two scores, but conceded 14 penalties to help Le Manu to a 25-16 victory at The Amex Stadium in Brighton.

Saracens man Wyles, who scored the States' first try to become the 100th captain to go over in a World Cup, said it was a tough pill to swallow.

"At times we physically matched them, but to be honest right now it's difficult to take a huge amount of positives away from that because our discipline let us down and our execution at times," he told Sports Mole.

"At the end of the day we were still in a position to win that game, which is a huge positive. We were close to winning and obviously even closer to getting the bonus point (teams losing by seven points or fewer get a point in the pool stage)."

The Eagles now have a week off before their second Pool B fixture against Scotland at Elland Road in Leeds.