Spain and Belarus took a firm grip of their Davis Cup quarter-finals, both racing to a 2-0 lead after Friday's opening singles.
While Juan Carlos Ferrero and Carlos Moya helped Spain to live up to their billing as favourites with easy victories over The Netherlands, World Group debutants Belarus capitalised on the absence of Argentina's two top players in Minsk.
Switzerland and France were locked at 1-1 in Lausanne after world number one Roger Federer swept past Nicolas Escude 6-2, 6-4, 6-4 before Arnaud Clement drew the visitors level with an equally impressive 6-3, 6-3, 6-2 win over Ivo Heuberger.
The United States and Sweden also shared the opening-day spoils at Delray Beach, Florida, Andy Roddick hauling the hosts level after Jonas Bjorkman had put his team 1-0 up.
Playing his first match in Switzerland since becoming the first player from his country to top the men's rankings, Federer was cheered on by a boisterous partisan crowd as he ruthlessly dismantled Escude's game.
"The reception from the crowd was amazing but it also made me very nervous," said the Wimbledon and Australian Open champion.
"It was a hell of an atmosphere but I am happy the match is over and that I have won the point."
Swiss captain Marc Rosset's gamble of picking Heuberger ahead of Michel Kratochvil for the second singles backfired as the world number 133 failed to keep pace with the flamboyant Clement.
France are bidding to avenge their defeat by Switzerland at the same stage last year. The winners will almost certainly run into Spain, last year's finalists, in the last four.
Moya secured a confident 6-2, 7-5, 6-4 victory over Dutchman Martin Verkerk, the man who beat him in the quarter-finals of last year's French Open, while world number three Ferrero cruised to a 6-2, 6-2, 6-4
AUTHORITATIVE PERFORMANCE
Despite a recent lay-off with chicken pox, Ferrero hit form from the start, easily holding serve and putting Sluiter under pressure with his whiplash returns and pin-point passing shots.
Ferrero used his full repertoire of ground strokes to work his opponent around the clay court, winning in one hour 50 minutes.
Another local-born favourite, Rafael Nadal, could clinch the tie for Spain with partner Tommy Robredo against John Van Lottum and Verkerk in Saturday's doubles.
Argentina, without top players Guillermo Coria and David Nalbandian, struggled from the start as Agustin Calleri and Guillermo Canas failed to come to terms with the fast carpet surface chosen by the hosts.
Vladimir Voltchkov, the architect of Belarus' surprise first-round victory over 2002 champions Russia, upset the formbook to beat Calleri 6-3 6-4 6-2 while Belarussian number one Max Mirnyi charged to a 6-2, 6-2, 6-2 win over Canas.
Playing in the World Group for the first time in their history, minnows Belarus appear well placed to face Sweden or United States in the semi-finals in September.
Bjorkman, the main pillar of Sweden's surprise win over holders Australia in the first round, gave his team a positive start against the U.S. by beating Mardy Fish 4-6, 6-3, 6-2, 7-5.
But world number two Roddick levelled the match for the Americans with a 6-4, 7-5, 6-2 victory over Thomas Enqvist.
Roddick and Enqvist had a lengthy wait to engage their rivalry after the Bjorkman-Fish encounter was interrupted three times by rain.
