Party of five

WHEN JUAN MARTIN DEL POTRO returned to Argentina following Wimbledon, he received a hero's welcome in his hometown of Tandil. As del Potro made his way through the bustling downtown streets, fans honked their horns and followed him with cellphone cameras, begging for photos. "It was like I played an Argentina soccer match," he says.

Andy Murray took home the silver cup, but the 24-year-old del Potro treated fans to the match of the tournament. Facing No. 1 Novak Djokovic in the semifinals, the 8-seed lost heroically in a record-setting 4-hour, 44-minute epic that may be an early sign of a crack in the logjam atop the rankings.

Since the 2010 U.S. Open, some combination of Roger Federer, Rafael Nadal, Djokovic and Murray has played in the finals of all but one major. But the 6'6" del Potro put the Big Four officially on notice with a single 113 mph crosscourt forehand in the fourth set that left Djokovic doubled over in exhaustion. He then evened the duel at two sets apiece by triumphing in a tiebreaker for the ages that included a 24-shot rally, two Hawk-Eye reviews and a pair of match points. In the fifth set, Djokovic capitalized on an overcooked Delpo forehand to pull out a break and win the match. Still, with both men lying in the locker room sheathed in ice packs, del Potro knew he'd made a case for being the comeback story of the season. "At the net, Novak said to me: 'You are a fantastic player. The crowd loves you,'" del Potro recalls. "For me, it was a fantastic moment."

It's not the first time del Potro has knocked on the top four's door. In 2009, when he upset Nadal and then Federer to win the U.S. Open, he looked as if he might be the man to mix up the upper echelon of the ATP. Instead, del Potro saw his No. 4 ranking at the start of 2010 plummet to 485 following wrist surgery later that year. He's been clawing back ever since, rising to No. 7 after Wimbledon. "I was ready for my chance," he says. "I was ready to head to another final."

He'll likely have that chance in the near future. Federer is ranked fifth for the first time in a decade as he toys with larger racket heads in hopes of finding new power. No. 4 Nadal spent July in Spain recovering from a first-round upset in London that raised new questions about his oft-problematic knees. And at 31, David Ferrer looks as if he's doing a guest spot at No. 3 until his Energizer battery runs out.

All of this leaves a much-needed opening for upward mobility in men's tennis. "I know how strong my game is," says del Potro, who has become a deadly counterpuncher and an unruly attacker. "I know good ways to beat them. But I need to work harder than them to be ready and wait for my opportunity."

Del Potro shines on the hardcourts, as his prior win over Djokovic at Indian Wells in March shows. And the Argentine is determined to keep his comeback going in Flushing, which he says gives him something close to a home-court advantage.

"The crowd [in New York] has something special with me, and I have something special with them," he says. "I'm ready to do another great surprise in the U.S. Open."

The fans are ready for it too -- only they won't be calling it a surprise this time.

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