Samoa have won their first match of the Rugby World Cup after defeating USA 25-16.

The teams had met four previous times, with Samoa triumphing in all four, but USA had never lost by more than seven points against their opponents. A series of penalties conceded by the USA was the difference with the teams both scoring two tries.

Samoa got three points on the board in the ninth minute when Jack Lam was brought down illegally and Tusu Pisi's kick was on target.

It was a tight opening 20 minutes of the match, and Pisi missed his second attempt at the posts in the 16th minute.

They scored the game's first try four minutes later though when Tim Nanai-Williams picked up a Pisi grubber kick to touch down

The conversion was missed but that did not stop Samoa extending their lead to 11 points seven minutes later. With USA penalised for not releasing, Pisi put the ball through the posts.

Just as it looked like Samoa might dominate the match, USA found their rhythm. AJ MacGinty pulled three points back after Samoa were caught offside.

USA captain Chris Wyles scored a well-worked try just two minutes later, crossing the line after a series of passes amongst the American backs.

Pisi put another penalty through the posts just before half time to give Samoa a six-point lead.

Samoa asserted their dominance in the second half, and scored their second try of the match when Ofisa Treviranus claimed a loose ball to give Samoa a 19-8 lead.

Penalties proved costly for USA and they gave another one away in the 50th minute when Andrew Duratalo committed a high tackle. Pisi extended the lead from in front of the posts.

AJ MacGinty took USA into double figures when he was on target after a Samoa foul, but that was cancelled out when substitute Michael Stanley kicked through the posts from the sideline.

Replacement Chris Baumann crossed the line in the 74th minute as USA sensed a comeback and MacGinty had the chance to come within a score of Samoa. He missed the conversion though and Samoa ran out 25-16 winners.