Of all the spectacular records Rafael Nadal holds, one of the most staggering yet least known is this: He has never lost a best-of-five-sets match on clay.
Yes, never. Not in 43 career matches, including four straight French Open victories, several Davis Cup ties and -- until 2007 -- finals of Masters events as well as selected other events like Barcelona and Stuttgart.
That immaculate record will be on the line again this week as Spain begins its Davis Cup defense on clay at home in the coastal city of Benidorm. Nadal will be on the squad, having recovered from a knee tendon problem that kept him out of the Barclays Dubai Tennis Championships last week.
He spent some of his unscheduled time off indulging his other sporting passion, soccer. Nadal was honored by the Mallorcan soccer team during a Spanish league match and also attended a Real Madrid game against Liverpool last week.
The break also allowed Nadal to be one of the first to arrive in Benidorm for the tie. "I feel very well, eager to defend my country," he said after a team training session over the weekend. "The court is perfect."
That will be a relief for new team captain Albert Costa, who is hoping to make a successful debut despite being handed a very tricky opener against Serbia.
After Roger Federer pulled out of Switzerland's tie against the United States, Spain versus Serbia became easily the biggest matchup of the first round. The nation that wins this weekend will be the heavy favorite to go all the way to December's final.
The Spanish Armada has not lost a home tie in nearly a decade, and showed its depth and versatility last year by winning the final on indoor hard courts against Argentina despite the absence of an injured Nadal.
Fernando Verdasco, the hero of that tie, is missing this time around, but Spain still has a strong lineup behind the returning Nadal: David Ferrer, Tommy Robredo and Feliciano Lopez. Ferrer or Robredo is likely to fill the second singles spot, and Lopez will bring his attacking skills to the doubles.
But with world No. 3 Novak Djokovic and doubles No. 4 Nenad Zimonjic, Serbia is one of the few nations that can hope to challenge the Armada. The Spaniards are aware their status as favorites depends heavily on two things: home-court advantage and the presence of Nadal.
The Serbs know it, too. Janko Tipsarevic, currently the third-ranked Serbian in singles behind Victor Troiki, sees Spain having a "60-40" or "70-30" chance thanks largely to Nadal's formidable clay record. "It is a great advantage, especially at home with 15,000 or 16,000 fans," Tipsarevic told DPA. "But if Nadal does not play, it makes a big, big difference.
"Because then we should win [Djokovic's] two singles ... and though I don't want to put pressure on Novak, [we] are the slight favorites against any doubles team put up by Spain."
But overall, percentage calculations will be less relevant to Serbia's fortunes than the physical condition of Djokovic, who is just as vital to his team as Nadal is to the Spanish side.
Winning the title in Dubai last week was a significant mental boost for Djokovic, but he was huffing and puffing during the final and had only one day off at home before having to fly to Spain for the tie. Considered suspect early in his career, his stamina re-emerged as an issue this year after he retired during his Australian Open quarterfinal against Andy Roddick because of the heat.
Coincidentally, Djokovic's opponent in the Dubai final was none other than Ferrer, but Djokovic is not expecting a repeat of last week's easy victory if the two meet again this weekend.
"David's going to be favorite in that match, to be honest, if we play against each other," said Djokovic in Dubai.
He might have been bluffing -- Tipsarevic would think so -- but it shows just what Serbia is up against: If Nadal wins his first match, as expected, a loss from Djokovic would put the Serbs down 2-0 right off the bat. (In Davis Cup ties, the top player from each team meets the second-ranked player from the opposing team in Friday's opening singles. If the contest is still alive after Saturday's doubles, the top players on each team face each other in the first match on Sunday, followed by the second-ranked players.)
When the Davis Cup draw was made last fall, Djokovic's father raised eyebrows with his farfetched accusation that things had been rigged against Serbia to prevent the young nation from making its mark in the competition.
Djokovic has stayed away from such discussions, but the pugnaciously patriotic Serb is also determined not to be daunted by the task at hand. "One thing is for sure, we are not going there to just play some good tennis," he said. "I think we have quite a young team, which can really challenge every team in the world and on every surface."
Neutral observers will be hoping that the contest stays alive until the reverse singles on Sunday, when Nadal and Djokovic could face each other in what would be the highlight of the tie.
Nadal has won 10 of their 14 meetings, including two wins on clay at Hamburg and the French Open last year that seemed to drain the Serb's energy for months afterward.
Djokovic may want to think about the curious fact that he shares a name with the only player ever to have beaten Nadal in a Davis Cup singles match: Czech Jiri Novak, who subdued the Spaniard on a fast carpet court in 2004.
But that was very early in Nadal's career. He had yet to turn 18 and had yet to play a Davis Cup match. In fact, he had yet to even play a best-of-five match on clay.
Djokovic will not want to think about what has happened since.
Kamakshi Tandon is a freelance tennis writer for ESPN.com.