Roughly 24 hours after the magic of Agassi and Blake began, Roger Federer put the finishing touches on a tired day of tennis, a nine-hour hangover following a night of revelry.

As the final weekend of the U.S. Open approaches, the 24-year-old Federer has begun to gather steam. His victim last night, Argentine David Nalbandian, had once been a nemesis, both as a junior and during their first five meetings as professionals. No more. Federer, who walked off with a 6-2, 6-4, 6-1 victory in an hour and 40 minutes, has won his last three meetings with Nalbandian. The world no.1 looks as invincible as ever, even if he has been watching a little too much television.

“I was up myself until 1:30,” he said when asked about Wednesday evening’s remarkable match. “Maybe it wasn’t the best preparation, but I enjoyed it.”

Nalbandian did not enjoy more than a few minutes of this quarterfinal contest. He broke serve in the opening game, but promptly lost the next four. He broke serve in the second set and held for a 4-2 lead, then lost another four games. And then another five. When he double-faulted to give Federer a match point and a chance for a 6-0 final set, the crowd booed. This encore just would not do.

It suited Federer well, however. He struggled (at least by his standards) in his previous two matches, but now seems to be rounding into form. He sliced well last night, rolled his backhand passing shots perfectly, and at times overwhelmed Nalbandian with his forehand. By the look of things, Federer is all but certain to become the first man in Open Era to win both Wimbledon and the U.S. Open in consecutive years.

Lleyton Hewitt would like to prevent that, and interrupt an eight-match losing streak against Federer. Hewitt, whose loss to Federer in last year’s final included two sets at love, survived his second five-set match of the tournament, this time against Finnish lefty Jarkko Nieminen.

Though Hewitt said he did not watch the previous evening’s festivities, he looked like he had. Normally feisty and relentless, Hewitt played sluggishly in the first and third sets. All tournament long, in fact, he has been more quiet than usual, often choking back his trademark “C’mon!” He knows he will need to do much more than he did yesterday if he plans to return to the finals.

“There’s no doubt I’ve got to go out there and execute what I want to do and play extremely well to go with [Federer],” Hewitt said. “No one’s been able to find the exact formula to topple him just yet.”

It’s not likely that anyone will, either.