Who needs Rafael Nadal when you have Feliciano Lopez…and Fernando Verdasco?

Going into the 2008 Davis Cup final, the question was how Spain could win without Nadal, but two days later the question is now the one above.

Argentina took an improbable 2-1 lead over host Argentina on Saturday afternoon in Mar del Plata as Lopez and Verdasco defeated David Nalbandian and Agustin Calleri 5-7, 7-5, 7-6(5), 6-3 in three hours and 18 minutes. The victory puts the Spanish squad on the brink of victory heading into Sunday’s reverse singles.

Argentina originally scheduled for Calleri to play with Jose Acasuso, but that was when the host nation was planning on having a 2-0 lead after Friday’s singles matches. When the favorites found themselves tied up after Day 1, they decided to go with Nalbandian.

The move paid dividends in the first set, as Nalbandian and Calleri seized a decisive service break at 5-5 before serving out the opening frame of play. Spain, however, turned the tables in set two, holding at 5-5 and breaking to level the match.

That set up a thrilling third set in which the Spaniards raced to a 4-0 lead that seemingly would have no chance of being overcome. Spurred on by an energized crowd, the Argentines refused to go away and broke back twice for 5-5. Calleri and Nalbandian then stormed to a 4-0 lead in the ensuing tiebreaker before it all collapsed over and around them. Nalbandian missed an easy backhand volley at 5-3 and Spain won the next three points for a two sets to one advantage.

This time, the Argentine duo could not recover. Lopez and Verdasco, who are an experienced doubles duo and play regular on the ATP Tour, really started to show their team unity, while that of Nalbandian and Calleri deteriorated. “They began to help each other less and less,” Lopez explained. “I was physically down in the third set and Fernando helped me. They did not do that, maybe it’s because we know each other better.” The experienced Spanish team used two more service breaks to finish off the match in three hours and 18 minutes.

Aside from what actually took place on the court, the Argentine fans were far more out of control than they were on Friday. “The crowd didn’t behave well today, they were using bad words and insulting us,” said Spanish captain Emilio Sanchez following the doubles rubber. “I’m disappointed in the way they behaved but we know now and we’ll be ready for tomorrow.” Verdasco, who took the brunt of most of the verbal jabs, added “they actually motivated me and allowed me to play better and their strategy totally backfired.”

“This is Davis Cup, this is normal,” retorted Calleri. “Maybe they went too far. I don’t think they were insulting Verdasco but I don’t know.”

Whatever the case, they will be even more obnoxious with their team against the wall on Sunday. It’s do or die for Juan Martin Del Potro when the hero of Argentina’s semifinal Davis Cup win over Russia battles Spain’s David Ferrer to kick off the action on Sunday.

Ferrer leads the head-to-head series with Del Potro, but the 6’6” Argentine won most recently in Tokyo just last month. That, of course, was when Del Potro was healthy and on top of his game. The 20-year-old exploded onto the tennis scene almost out of nowhere, winning every single one of the four tournaments he played in between Wimbledon and the U.S. Open. Fatigue and a foot problem hobbled Del Potro throughout the recent indoor swing, however, and a thigh problem crept up to bite him in his four-set loss to Feliciano Lopez on Friday.

Ferrer’s 2008 campaign went south just as Del Potro’s took a turn for the better. The first half featured outstanding tennis from the Spaniard and kept him firmly entrenched in the Top 10. He reached the quarterfinals of the Australian Open and the French Open and won smaller clay-court titles on both clay and grass. Beginning with the U.S. Open Series, however, Ferrer endured a dismal slump. He now finds himself outside the Top 10 at No. 12 in the world, and on Friday he was not competitive in a three-set loss to Nalbandian.

The first few games of this clash will tell the story. If Del Potro is healthy, a dramatic come-from-behind victory for Argentina could be in the cards. If he is hobbled, Ferrer will grind and grind until Del Potro goes down and Spain has the Davis Cup trophy in hand.

Rumors, not surprisingly, are swirling that Jose Acasuso will replace Del Potro against Ferrer. That won’t be good news for Argentina, but it might have to be done…and it could be worse. After, Acasuso leads his head-to-head series against Ferrer 4-3, although six of the seven encounters have come on hard courts. Acasuso’s 2008 season, however, has been mostly uninspiring, especially away from clay. He would be a considerable underdog against Ferrer, but still a better option than an injured Del Potro.

If Ferrer wins the 2008 Davis Cup for Spain with a win over Del Potro, Lopez and Nalbandian probably won’t even take the court. At most it would be a “dead” rubber. If Del Potro keeps the host nation’s hopes alive, however, Lopez and Nalbandian will battle in one of the biggest matches of the entire tennis season.

In that case, the advantage would be squarely back in the Argentine corner. First, Nalbandian has a perfect 2-0 head-to-head record against Lopez. Furthermore, Nalbandian has recently resurrected a year that started off slowly. During this year’s indoor swing, he won a title in Stockholm and finished runner-up in both Basel (to Roger Federer) and Paris (to Jo-Wilfried Tsonga).

At the same time, Lopez is a formidable opponent. An experienced Davis Cup participant, Lopez is one of the few Spaniards in the history of the game who actually prefer fast hard courts over clay. Lopez’s first half of the 2008 was mostly lackluster except for a surprising runner-up finish in Dubai, but he started to turn it all around at Wimbledon and during the hard-court swing. Lopez reached the quarterfinals at the All-England Club, the semifinals in Vienna, the quarterfinals at the Masters Series Madrid, and the semifinals in Basel. He has himself back in the Top 32 in the rankings (at No. 31) and in position for a seed at the Australian Open.

If this rubber is “live,” look for the Argentine crowd to carry Nalbandian to a dramatic Davis Cup-clinching victory.

“The team is logically down but we have to go through that,” said Argentine captain Alberto Mancini. “We have to wait and stay quiet and plan. Maybe the immensity of the event was too much for my players. We still have to fight, there are two more points tomorrow and we know it will be hard.”