( dpa ) - Stefan Koubek earned a face-saving point for beaten Austria on Sunday as cramping Mike Bryan retired to hand over a 7-5, 1-0 victory in their dead rubber at the Davis Cup World group tie.
With Andy Roddick and James Blake flying back to the United States on Sunday, captain Patrick McEnroe had no choice but to play his two doubles aces in the meaningless singles.
Twin brother Bob Bryan was facing Austrian Werner Eschauer to wrap up the weekend.
The US faces an April 11-13 tie in North Carolina against France, which also clinched a place in the quarter-finals through doubles a day early on Saturday.
"It's tough to play a Grand Slam with Davis Cup right on the horizon, but these are the only real moments that get my juices flowing anymore," said Bob Bryan.
The US face France in Winston-Salem, North Carolina, the well-attended venue for a 2007 win over Spain in a region which sees no professional tennis on a regular basis.
"It was one of the best crowds we've ever had in the US," said US captain Patrick McEnroe. "We hope to fill it again and make it nice and loud and noisy for the French."
In Moscow, illness caught up with Novak Djokovic, as the Serbian world number three could not go on in his key singles rubber against Nikolay Davydenko.
World number four Davydenko clinched a quarter-final place for 2006 champion Russia as he won 4-6, 3-6, 6-4, with Australian Open winner Djokovic felled by the influenza which kept him out of Friday play.
France piled on another point to reach 4-0 against Romania, with Michael Llodra beating Andrei Pavel 7-6 (7-5), 7-6 (9-7) in the dead rubber.
Thomas Johansson pulled Sweden level at 2-2 at Ramat Hasharon versus Israel, beating Dudi Sela 7-6 (8-6), 6-1, 7-5.