San Jose - In a sneak preview of their opening match of the 2015 Rugby World Cup, world No 9 Samoa kicked off their Pacific Nations Cup campaign on Saturday with a 21-16 win over the US.
Samoa, who dropped a close 25-16 decision to top ranked New Zealand earlier this month, jumped out to a 21-3 half-time lead against the Americans then held on for the victory at Avaya Stadium.
The Samoans used just five players from their game against the All Blacks.
Samoa and the 16th ranked USA open their World Cup quests with a match against each other on September 20 at the 30 750 seat Brighton Community Stadium in England.
In the earlier Pacific Nations Cup game, Japan easily defeated Canada 20-6.
The Samoans were led by the Tuilagi brothers - former Leicester Tiger Alesana Tuilagi and Vavae Tuilagi, who is the sixth member of his family to play international rugby.
Outside half Patrick Faapale converted three penalty kicks in the opening 24 minutes as Samoa jumped out to a 9-3 lead.
Captain Alesana Tuilagi capped a long march up the field by taking a handoff from teammate Ah See Tuala before running through a crowd of defenders to make it 14-3 with about nine minutes to go before the half.
The Americans outscored Samoa 13-0 in the second half but they couldn't overcome their poor start as their late rally fell short.
The US and Samoa will join Japan, Scotland and South Africa in Pool B of the World Cup.
Japan captain and all-time leading point scorer Ayumu Goromaru booted five penalties and Yoshikazu Fujita had the only try of the game against Canada.
Gordon McRorie kicked two penalties to account for all of Canada's points.
Goromaru put Japan ahead after just eight minutes, but Canada responded with sustained pressure, Van Der Merwe getting around the Japanese line before his offload fell into the wrong hands.
Canada couldn't convert and Japan scored what proved the lone try of the game in the 16th minute.
Kotaro Matsushima darted through the Canadian line and his offload found Fujita, who cruised in for his 25th test try.
Goromaru couldn't add the conversion, leaving Japan up 8-0.
Canada responded with McRorie converting his first penalty of the game after Hitoshi Ono was penalized.
Goromaru extended the Japanese lead in the 29th minute to 11-3 and that is how the teams went into the locker rooms at the half.
The tournament had got underway earlier Saturday in Suva, where Fiji came from behind to beat Tonga 30-22 in the only match to be played in the Pacific.
All the remaining matches will be played in North America, with the six sides split into two pools and the top two sides from each group playing for the Cup on August 3 in Vancouver.