Roger Federer and Rafael Nadal could face each other in the first round of next year's Davis Cup after Spain drew Switzerland on Wednesday.
Federer and Nadal, ranked respectively one and two in the world, have never met in the Davis Cup. They last played each other at the Madrid Open in May when Federer carried the day 6-4, 6-4.
The draw for the World Group also sends the United States to Serbia, making a match between Novak Djokovic and Andy Roddick a possibility.
The Czech Republic, which faces Spain in this year's final in December, will travel to Belgium.
On Sunday Federer clinched Switzerland's place in the 2010 Davis Cup World Group with a victory over Potito Starace in Genoa. The Swiss team beat the Italians 3-2 in the best-of-five play-off.
Winning the Davis Cup is one of the few achievements missing from Federer's long list of accomplishments.
swissinfo.ch and agencies
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