SHANGHAI - Roger Federer survived a furious onslaught by Andy Roddick to put one foot in the Masters Cup semi-finals.

Switzerland's Roger Federer returns a ball to American Andy Roddick during the Tennis Masters Cup held in Shanghai, China, Tuesday, Nov. 14, 2006. Federer won 4-6, 7-6(10-8), 6-4. [AP]

The world number one dropped the first set and saved three match points in a tense second-set tie-break before running out the 4-6, 7-6 (10/8), 6-4 winner.

Federer, who last met Roddick in the US Open final, extended his winning streak against the American to eight matches going back more than three years.

Andy Roddick of the U.S reacts during his match with Roger Federer of Switzerland in the Masters Cup tennis tournament in Shanghai, November 14, 2006. [Reuters]

The 2003 and 2004 champion is all but qualified for the last four here after the win, to go with his straight-sets win against David Nalbandian.

The match also made him the first player to earn more than seven million dollars in a season, with career earnings of more than 27 million dollars.

But Federer, who has never lost a Masters Cup round-robin match, can count himself lucky after being rattled by the big-serving American for the first two sets.

"I played well enough to win tonight, let's not let that be lost," said Roddick, who has turned his season around under advisor Jimmy Connors.

"I felt like I was the better player for two sets tonight so if I can keep building on that and keep improving at the rate I have over the last three or four months, hopefully we can get over that last little hump."

Blasting eight aces in the first set and unsettling the Swiss with frequent visits to the net, Roddick won the decisive break on a double-fault in the third game.

Roddick escaped two break points and, serving for the set, survived a brief attack of the nerves as he converted his third chance with a backhand volley.

Federer saved another break point at 2-2 in the second and had Roddick on the ropes at 5-4, but the American escaped three break points.

Tension grew in the Qi Zhong Stadium as the set went to a tie-break and Federer survived three match points.

His relief was palpable when Roddick momentarily lost his cool with a wild jumping volley on Federer's second set point, tying the match at 1-1.

After breaking Roddick in the third game of the decider, there was only going to be one winner and Federer converted his second match point with his third ace of the last game.

Federer also beat Roddick in the 2003 semi-finals in Houston on the way to his first Masters Cup title. He is bidding to become the event's first triple champion.

Nalbandian was playing Ivan Ljubicic in Tuesday's later Red Group match.