NEW YORK (AP) — Locked in a taut, thrill-a-minute second set, Novak Djokovic and Juan Martin del Potro headed to a tiebreaker and produced a 20-stroke masterpiece of a point befitting a pair of past U.S. Open champions.
More than a dozen shots in, defending champion Djokovic drew del Potro forward with a drop shot, then tossed up a lob. Del Potro, the 2009 champion, sprinted with his back to the court, got to the ball and lofted a lob the other way. Djokovic slammed an overhead. Del Potro somehow kept the ball in play. Djokovic laced a drop shot. Again, del Potro got there, attempting another lob. It landed long.
A point from a two-set lead, Djokovic threw his head back, roared "Come on!" and pumped his arms. Del Potro leaned his elbows atop the net, hunched over and rested his head on his arms.
Close and compelling as their quarterfinal was, it might as well have been over right then and there. Djokovic's down-the-line backhand winner seconds later ended the tiebreaker and gave him a commanding lead on the way to a 6-2, 7-6 (3), 6-4 victory over del Potro on Thursday night that put the Serb in his 10th consecutive Grand Slam semifinal.
"We played some incredible rallies and incredible points," the second-seeded Djokovic said. "It's always entertaining, always so much fun, playing in these night sessions."
Djokovic will face fourth-seeded David Ferrer on Saturday, with a spot in Sunday's final at stake. Ferrer advanced to his fourth career major semifinal by using his own version of leg-churning, ball-chasing tennis to outlast eighth-seeded Janko Tipsarevic of Serbia 6-3, 6-7 (5), 2-6, 6-3, 7-6 (4) in 4 hours, 31 minutes.
Olympic champion Andy Murray and 2010 Wimbledon runner-up Tomas Berdych — who eliminated 17-time major champion Roger Federer — earned their semifinal berths Wednesday.
Ferrer needed a mid-match pedicure of sorts, seemed bothered when Tipsarevic got a mid-game medical timeout and, worst of all, was down 4-1 in the fifth set.
In the end, though, the indefatigable Spaniard was barely better, as he usually is when matches go the distance. He has won four consecutive five-setters and is 17-9 overall.
"I don't have words," said Ferrer, who reached the semifinals at the French Open in June. "It was a very emotional match."
When it ended on Tipsarevic's backhand into the net, Ferrer raised his arms, then knelt near the baseline. The weary foes met at the net for a hug.
"David is a fighter. He is one of the biggest competitors we have in the game. People ... overlook him," Djokovic said. "You need to earn your points against him."
Hmmmm. Sound familiar?
Del Potro might use those exact words to describe Djokovic.
Under the lights at night in Arthur Ashe Stadium, the showcase matchup of Djokovic's squeaky-sneaker defense, reflex returns and line-catching groundstrokes against the seventh-seeded del Potro's big-as-can-be forehands topping 100 mph lasted a little more than three hours. It was tremendously good every step of the way, and the second set alone was 84 minutes long — 11 minutes more than Djokovic's entire first-round match last week.
"Crucial," Djokovic said about Thursday's second set. "It could have gone either way."
Djokovic and del Potro, a 6-foot-6 Argentine, each was left smacking himself in the head with a racket after an ugly mistake — the shot-making was so high-caliber that any miscue really stood out. The full house responded more than once with standing ovations, but the loudest and longest came before the tiebreaker.
These are the only two men who have managed to beat Federer and Rafael Nadal, owner of 11 major trophies, in the course of a single Grand Slam tournament. Djokovic and del Potro each did it while on the way to the championship at Flushing Meadows.