In Davis Cup all things are possible and the United States team just proved it in Switzerland.

Without Andy Roddick, their banker over the past decade; without half of their talismanic doubles team; made to play on a specially laid clay court indoors at the Fribourg Forum and facing Roger Federer, Jim Courier's team surprised themselves and shocked the tennis world by establishing a 3-0 winning lead after just two days play.

If John Isner's fantastic four-set victory over Federer in Friday's second singles was one of the least expected results in recent Davis Cup history, it was Mardy Fish who stepped up big-time for the US -- beating Stan Wawrinka in a marathon five-set first rubber and then filling Bob Bryan's shoes to team with Mike Bryan in a doubles match against Federer and Wawrinka that the Americans dominated with surprising ease. The final score was 4-6, 6-3, 6-3, 6-3 and even though the scratch pairing managed a Bryan-style chest bump at the end, everyone in the American camp looked a little disbelieving.

"We are pleasantly surprised," said Courier, who came of age as a Davis Cup captain in this tie. "We were on a mission and came here with a clear message -- to be focused and play aggressive tennis. And we did that. It was a sweet victory but we had to earn it."

They certainly did. No Davis Cup tie played away from home on a surface chosen by the opposition is ever easy and given the quality of the players facing them and the US record of losing away on clay, this had appeared to be a peak too high to climb in the Swiss Alps for a depleted team.

But much of the team spirit built up during Patrick McEnroe's long tenure as captain has obviously been carefully fostered by the popular Courier who commands instant respect as the winner of four Grand Slam singles titles during his playing days.

Teenager Ryan Harrison had been penciled in as Mike Bryan's doubles partner when the teams were announced but as soon as Fish told his captain he felt fresh enough to handle the task in hand, there was never any doubt that Courier was going to go for the jugular and throw in his best combination. The 0-2 scoreline from Switzerland's point of view also ensured that Federer would be called into doubles action to play alongside his Olympic gold-winning partner Warwinka.

It started well for them when Fish played his only bad game of the match and dropped serve in the opening game. "We came out a little nervous," admitted Bryan. "But Mardy is a clutch player and he played a little bit like Bob!"

Back home, helping to care for his newborn daughter, Bob Bryan must have smiled at that. But one thing is certain, the new father will be back on duty for the next round against the winners of the tie between France and Canada.