Top seed Federer, coming into Shanghai with an impressive 11 titles this season, rallied from one set down to destroy Argentine nemesis David Nalbandian 3-6, 6-1, 6-1 in a blockbuster opening match to the 2006 curtain-closer.

While Roddick, the US Open beaten finalist, also battled back in full sets to subdue the Croatian number one Ivan Ljubicic in two hours and 29 minutes, one more hour than Federer.

"Probably a couple of years ago I wouldn't know what to do (while trailing behind), but through the mental and physical strength I was able to overcome all these problems. Now I just hang in there and hope for the best," said Federer at the post-game press conference after beating Nalbandian.

In doubles' action, American Bob and Mike Bryan, the world's best doubles team, lost 7-6(2), 2-6, 6-1 to Jonathan Erlich and Andy Ram, who won four titles this year and are the first Israelis to reach the tennis Masters Cup elite.

World number one Federer, attending the season-ending jamboree for the fifth consecutive time, did not hit his stride in the opening set, allowing seventh seed Nalbandian two breaks to concede 6-3 in 45 minutes or so.

"In the first set he (Nalbandian) could really take my second serve easily, also from the baseline he had an upper hand at the moment. He is a top player and keep a good consistency, and he won the set."

The Swiss champion, however, woke up in time to draw first blood in the second set breaking early to go up 2-0 and never looked back before taking the set 6-1.

Nalbandian, who came back from a two-set deficit to wrest the crown from Federer here last year, dramatically lost his steam before collapsing in the third set 6-1 too.

"It is very happy to come through a guy like Nalbandian. You know, it is difficult to play against him. I don't feel much revenge because he can come back and beat me again in semifinals or the final if he played well. Let's see what happen in the next few days."

Fifth-seeded Roddick, who has gone ten months without a title since he reeled in the Masters Series Cincinnati trophy in August, squandered two match points in the second set tie-break before beating fourth seed Ljubicic 6-4, 6-7(9), 6-1 in the Red Group dubbed as the "Group of Death".

"I hear that everybody was calling this group 'the Group of Death'. The way I see it, only two people are dying, so I don't want to be one of them," said Roddick.

"I thought I served well and I thought I returned well. I still think I can hit the ball a little bit better from the baseline. Overall it was a pretty solid performance."