Juan Martin del Potro after his victory over Rafael Nadal at Flushing Meadows on Sunday. (Reuters)

New York: Argentina’s Juan Martin Del Potro bludgeoned Rafael Nadal 6-2, 6-2, 6-2 at the US Open on Sunday to reach his first Grand-Slam final.

The sixth seed overpowered the Spaniard in two hours, 20 minutes of outstanding hitting to set up a final against either five-times champion Roger Federer or fourth seed Novak Djokovic of Serbia.

The first set was a story of missed opportunities as Nadal squandered three break point chances, while the Argentine broke twice, in the fourth and eighth games.

The pattern was repeated in the second set and though Nadal continued to fight in the third, Del Potro was too strong and cruised to a comprehensive victory.

Earlier, Caroline Wozniacki warmed up a couple times, read a book and talked to her friends and family as she waited for her semi-final to start Saturday. She even managed to take a nap.

This Great Dane is one cool customer.

Wozniacki advanced to her first Grand Slam final with a 6-3, 6-3 victory over Yanina Wickmayer, using her speed and steady play to overcome an early break in the final set.

“'It’s a dream come true to play the finals of a Grand Slam, and now I’m here,” a beaming Wozniacki said. “So I mean, I have absolutely nothing to lose.”'

The No. 9-seeded Wozniacki converted six of 11 breakpoint chances in the matchup of emerging 19-year-olds and will play Kim Clijsters on Sunday for the title. Clijsters, the 2005 champion, advanced with a 6-4, 7-5 victory over Serena Williams.

Wozniacki, a native of Odense, Denmark, covered her mouth after Wickmayer’s forehand landed wide on the final point, and nearly broke down as she approached the net. She won the final four games of the match as Wickmayer struggled with her groundstrokes.

“'She made not any mistakes,”' said Wickmayer, who committed 40 unforced errors to 14 for Wozniacki. “'She just kept bringing the ball back and back. ... She was really fast.”'

The long weather delay and marquee matchup on the US Open’s main court set up a surreal scene at Armstrong Stadium, with a sparse crowd of about 500 in the stands at the start of the semi-final. After the pre-match music stopped and before Wozniacki and Wickmayer walked through the tunnel, a concerned fan shouted “Quick, before it rains again.”

Oops, too late.

Wozniacki walked to the net after the first point to complain to the chair umpire about the slick surface, and play was stopped for about 10 minutes while a light drizzle fell.

With the players waiting under umbrellas in their courtside chairs, a man shouted nervously “It’s my wife’s birthday,” and the crowd responded with a cheery rendition of “Happy Birthday.” A boy moved to the front row to yell “I love you Caroline,” before sheepishly returning to his chair.

“Yeah, I smiled,” Wozniacki said. “I mean, what else can I do?”

Wozniacki jumped all over Wickmayer when play resumed, breaking her four times and closing out the set when the Belgian dumped a volley into the net.

Wickmayer went ahead 3-2 with a break early in the second set but couldn’t keep it up as Wozniacki turned up the pressure, setting up the match with Clijsters.

“We’re both fighters,” Wozniacki said. “We want to win. We want to, you know, win this Grand Slam, and it’s going to be a tough match.”

Meanwhile, top seed Yuki Bhambri’s title hopes went up in smoke after a stunning straight-set defeat to unseeded local favourite Chase Buchanan in the boys’ singles quarter final.

The match, delayed by a day due to persistent rain, ended in a heartbreaking 3-6, 6-7 (4-7) loss for the Indian, who had not dropped a set this far in the hard court event.

The match was shifted to indoor courts and the changed conditions perhaps adversely affected the reigning Australian Open champion.

The junior world No. 1 has already crashed out of the doubles following a shock first round defeat with his Taipei partner Liang-Chi Huang.

Buchanan then went on to win his semi-final against eighth seed Gianni Mina of France and set up a title clash against Australian third seed Bernad Tomic.