Spain stunned, Djokovic shines in Davis Cup

Top seeds Spain moved to the brink of a shock Davis Cup exit when their weakened team slumped to a 2-0 deficit at the hands of Canada in a world group, first round tie played on lightning quick Vancouver hard courts.

Novak Djokovic was in no mood for upsets, however, and earlier got right back in the groove after his Australian Open triumph with a crushing defeat of Olivier Rochus as Serbia surged into a 2-0 lead in Belgium.

Holders Czech Republic were locked at 1-1 after the first day against a Switzerland side minus world number two Roger Federer - Tomas Berdych levelling the tie after Lukas Rosol had been outplayed by Stanislas Wawrinka.

Germany's hopes of beating Argentina in Buenos Aires suffered a cruel blow, however, as Philipp Kohlschreiber was forced to retire with a hamstring injury when serving for the match at 5-4 in the fifth set against Carlos Berlocq.

A later win for Juan Monaco over Florian Mayer meant Argentina ended the day 2-0 ahead as did France and Kazakhstan in their ties against Israel and Austria respectively.

Croatia and Italy were locked at 1-1 in Turin while the United States took a commanding 2-0 lead over Brazil in Jacksonville after Sam Querrey dispatched Thomaz Bellucci in straight sets and John Isner thumped Thiago Alves.

Spain, five-times winners of the Davis Cup, were weakened by the absence of top 15 players Rafa Nadal, David Ferrer and Nicolas Almagro and the Canadians, who have never won a world group tie, pounced to take advantage.

Big-serving Milos Raonic was expected to bludgeon his way past Alberto Ramos and duly delivered when he sealed a 6-7 6-4 6-4 6-4 victory over the world number 51 with two thumping aces.

Frank Dancevic, ranked 161, provided the real shock of the day, though, humbling world number 34 Marcel Granollers 6-1 6-2 6-2 to give his country a 2-0 lead going into Saturday's doubles.

"I think I played the match of my life today," said the 28-year-old journeyman.

"I just went in with a lot confidence, like just had to go all or nothing today. Anytime I had an opportunity I went for it.

"This isn't over yet. We've (got) to go strong, these guys aren't finished yet, they're going to come strong tomorrow.

"They've got a great doubles team ... we just have to go hard until the last ball this weekend."