In theory, two players are all a country needs to win the Davis Cup. In practice, it almost never works out that way.
The drumbeat nature of the competition demands adaptability. Each annual Davis Cup competition takes place during the course of 10 months, and even the winning nation finds itself back in the first round just three months later. Inevitably, all teams have times when their top players are injured or absent. The hallmark of a consistently successful nation is one that can win with its B-squad and keep churning out new talent to replace outgoing stars.
Few countries have a deeper pool of talent than this year's finalists, Spain and Argentina.
The showdown between the world's two best clay-court nations ironically will be held on indoor hard courts, but no fewer than six French Open champions or finalists will be absent from the lineups for one reason or another.
Spain has named David Ferrer, Fernando Verdasco, Feliciano Lopez and (surprise!) Marcel Granollers to its team -- a respectable but not formidable lineup, considering the names it theoretically could have chosen from.
But the Spanish armada has been hit hard by injury and unpreparedness in the run-up to the Davis Cup final. Three current or former No. 1s are among those not present on the squad that has traveled to Mar del Plata, Argentina, for this weekend's tie:
Status for final: Injured
The most conspicuous absence is the world's top-ranked player, Nadal, who hurt his knee at the BNP Paribas Paris Masters two weeks ago. Nadal's legend has been built mostly on clay -- and now grass -- but as his victories at the Olympics and the Rogers Cup in Toronto this past summer showed, he can be formidable on hard surfaces when healthy.
And sometimes, even when not so healthy. Remember that a 19-year-old Nadal won the indoor hard-court Madrid Masters on sore knees in 2005. There was hope that the call of national duty would again push Nadal through the pain barrier, but three years later, he has endured a lot more wear and tear on those joints.
"I am used to playing with pain, but this is a different and new kind of pain," Nadal said when announcing he would not be able to play. "I cannot manage to control it."
Juan Carlos Ferrero
Status for final: Vacationing
Ferrero had an unforgettable debut in Davis Cup play, when he won his first five matches and clinched Spain's first-ever Cup victory in 2000 with an intense four-set battle against Australian Lleyton Hewitt.
The competition never again held such heady emotions for the quiet, proud Valencian, not even during the best season of his career in 2003: He won the French Open, reached the U.S. Open final and became No. 1 in the world. But that year, Spain fell to Australia on grass in the Davis Cup final. It regained the Cup the following year, but by then, Ferrero -- laid low by chicken pox and a rib injury -- had been relegated to a losing doubles role.
Although Ferrero has not managed to return to his former heights, he has been in and out of the top 20 and would have been a respectable replacement for Nadal. Though Nadal was injured at Rome in May when Ferrero got the better of him, there was a certain poetic symmetry in that the former king of Spanish tennis was the only player to bring down the current king of Spanish tennis on clay this year.
Spanish Davis Cup captain Emilio Sanchez reportedly asked Ferrero to fill in for the final, but no luck -- he already was on vacation in Brazil.
Status for final: Emeritus
Moya's serving as Nadal's substitute in this Davis Cup final would also have had a certain poetic symmetry. The French Open champion in 1998, Moya has been a friend and mentor since Nadal's earliest days as a pro, and the two Mallorcans teamed to win the Davis Cup final for Spain in 2004.
Still hanging in the top 50, at 32, Moya has outlasted all his Spanish contemporaries on the circuit. But he gave up on Cup competition after that dream victory in 2004 and wasn't an option for this tie.
Captain Sanchez has been criticized for having no Plan B in case Nadal could not play and for not arranging potential substitutes ahead of time. Tommy Robredo, the player considered most likely to replace Nadal, begged off, saying he had not trained in nearly two weeks because he was on his offseason break. Other possibilities such as Nicolas Almagro and Albert Montanes heavily favor clay, and in any case, Almagro is still rehabbing from wrist surgery.
Unlike Spain, Argentina's top choices are healthy and willing to play as the country goes for its first Davis Cup title. Juan Martin del Potro and David Nalbandian will lead the squad, and Jose Acasuso and/or Agustin Calleri potentially will play a role in the doubles.
But what of the names that didn't even make the short list? An astonishing number of Argentine stars have fallen by the wayside in recent years, and this tie will feature almost as much talent in the stadium as on the court:
Status for final: Commentator
It can be easy to forget that Coria did not, in the end, win the French Open. But he came awfully close. Coria had won 48 of his previous 50 clay matches going into the 2004 French Open final -- a mighty streak in those pre-Nadal days. Playing for the title, Coria led by two sets before being overcome by nerves and cramps, and he squandered two match points in a dramatic five-set defeat.
He was never the same again. The trauma of that loss was followed by a string of unfortunate events that saw Coria miss a full year of play between 2006 and 2007. He returned to the tour a year ago, but the psychological hangover of a shoulder injury was still playing havoc with his serve. He won just three matches before more problems forced him to take another break in July.
Still just 26, Coria is not ready to retire but also hasn't set a date for his return. He'll provide commentary for Argentine cable channel TyC Sports during the final.
Status for final: Commentator
The player who denied Coria the French Open crown in 2004 hasn't had much better luck. Gaudio kept up his form for a couple of years after his unexpected Slam victory but struggled all of last year and became so discouraged that he even flirted with retirement.
He decided to persevere and plans to be back next season, but the 29-year-old continues to be negative about his prospects. "Maybe in 20, 30 years I'll start to play well," he joked at last week's Copa Petrobas exhibition in Santiago, Chile.
Gaudio also may be in the commentary booth for the final, as Argentine broadcaster Canal 13 offered him a spot.
Status for final: Sparring partner
The curse of the Argentines and French Open finalists continued the following year with Puerta, who lost to Nadal in four sets in 2005 but eventually was suspended because he tested positive for a stimulant after his semifinal win.
Puerta initially was banned for eight years because it was a second offense, but the period was reduced to two years because both positive tests were ruled accidental -- the first was because of asthma treatment in 2003, and the second was traced to a menstruation medication his wife used.
Now 30, Puerta returned to the tour when his suspension ended in June 2007. He has been scratching it out in challengers ever since, struggling to get back into playing shape after gaining weight during his layoff. But Puerta is at Mar del Plata this week, taking part in the team's practice sessions -- and soccer matches, of course.
There's a fourth active former top-10 player missing from Argentina's ranks. Guillermo Canas, best known for defeating Roger Federer twice in a row back in the days when the feat was still rare (early last year), was on the team for the semifinal against Russia but was replaced by Acasuso for the final. Canas, ranked 78th, will turn 31 next week.
Former No. 15 Juan Ignacio Chela is also 31, and his ranking has dropped to No. 145. He's no longer a contender, but he did give the team a little break from training by inviting them all its members to his wedding last week.
Most notable is that Argentina's third-ranked player, Juan Monaco, also was not named to the team. Eduardo Schwank was passed over but is in Mar del Plata taking part in the tennis and soccer festivities.
Kamakshi Tandon is a freelance tennis writer for ESPN.com.