Andy Murrary secured the decisive victory to put the match beyond the Americans, with a 7-6, 6-7, 6-1, 6-3 win over Sam Querrey.

Querrey, ranked number 49 in the world, was a surprise loser to 175th-ranked Londoner James Ward in a five-set dual earlier in the Davis Cup tie.

Murray's win, which gave Britain an unassailable 3-1 lead, marked the country's first victory over the United States since 1935.

They will face Italy in the quarter-finals in Italy, in a tie likely to be played on clay.

British number one Murray had beaten Donald Young to get his country off to the perfect start in San Diego on Friday (January 31).

Sam Querrey, left, lost in five sets to James Ward, and in four sets to Andy Murray ©Getty Images



The doubles encounter yesterday saw Colin Fleming and Dom Inglot lose to the world number one Bryan brothers, of America.

Of his win against Querrey, Murray said: "Sam came out playing extremely aggressive, he was very aggressive on my serve.

"I changed tactics at the beginning of the third set and I was able to dictate a lot of points after that."

Britain's next opponent, Italy, beat Argentina 3-1 in their Davis Cup clash.