By Paul Casciato

LONDON (Reuters) - United States, chasing their first Olympic gold in women's volleyball, kept up their unbeaten record at the London Games with a 3-0 victory over Turkey on Sunday.

While the Americans wrapped up their Group B campaign with an unblemished 5-0 record, the Russians did the same in Group A thanks to a 3-2 win over Italy.

Hosts Britain, Turkey, Algeria and Serbia all went out of the competition.

Turkey gave the U.S. a scare early on and only lost the opening set 27-25.

"In the first set Turkey had a lot of success," U.S. coach Hugh McCutcheon told Reuters. "Once we locked our defense and our reception grooved in a little bit, that made things easier."

Destinee Hooker blasted 17 spikes out of 38 attempts, delivered 19 points and had strong help up front at the net from Foluke Akinradewo as the world number ones claimed the last two sets 25-16 and 25-19.

The U.S. women, who picked up a silver medal at the Los Angeles Games in 1984 and in Beijing in 2008, may have a concern over captain and triple Olympian Lindsey Berg after she appeared to be hobbling after the match.

The Americans meet Dominican Republic in the quarter-finals on Tuesday, Russia clash with Brazil, Japan take on China and Italy face South Korea.

EMOTIONAL FAREWELL

Britain, ranked 69th in the world, bade an emotional farewell to the tournament with a 1-4 win-loss record after losing to a far superior Japan who outclassed them at the net and in terms of ball reception.

Despite some impressive work at the net from Britain's Lynne Beattie and Ciara Michel, the more experienced Japanese side, ranked fifth in the world, won 25-19 25-14 25-12.

While Britain never really posed a threat, each point for the home side received a rousing cheer from their supporters.

The team held up a 'Thank You' message to the fans who have howled their support and stomped their feet at every match.

Japanese coach Masayoshi Manabe praised the improving British team who were playing in their first top-flight international competition.

Home captain Beattie said she felt her side had met expectations by beating 16th-ranked Algeria in their second match earlier in the event and putting up a good show against Japan.

"We go away from this tournament feeling like we can stick in there with the best teams in the world," Beattie told reporters.

Ninth-ranked Russia narrowly defeated world number four Italy in a see-saw battle that went to the fifth set.

Russia pulled ahead late in the decider to win 15-11, with top scorer Nataliya Gonchorova delivering 33 points in the match.

Coach Serguey Ovchinnikov told Reuters he delivered firm instructions to his Russian side after the opening set.

"When we lost the first set we had some problems with our attack," Ovchinnikov said. "I told them you need to correct your mistakes."

(Editing by Tony Jimenez)