Nadal tested at Flushing Meadows

Rafael Nadal withstood his first test at this US Open, shifting into another gear to beat Sam Querrey 6-2, 5-7, 7-6 (2), 6-3 and match his best result at the tournament that's always eluded him.

Rafael Nadal serves to Sam Querrey.

NEW YORK // Rafael Nadal withstood his first test at this US Open, shifting into another gear to beat Sam Querrey 6-2, 5-7, 7-6 (2), 6-3 yesterday and match his best result at the tournament that's always eluded him. Playing for the sixth year at Flushing Meadows, the No. 1-ranked Nadal rallied to reach the quarter-finals with his most vigorous workout of this year's championship. He got quite a scare from his unseeded, 20-year-old American opponent too.

"Very tough," Nadal said. "Sam is a big player, a big server. He has a great future." Down 6-5 in the third set, Nadal suddenly flashed the form that saw him win at Wimbledon, the French Open and the Olympics. Hitting harder, grunting louder and moving in closer, he quickly forced a tiebreaker and leapt to celebrate. Nadal won the final four points to take the tiebreaker and later served out the match.

The Spaniard will next play another unseeded American, Mardy Fish, who reached the quarter-finals at the US Open for the first time with a 7-5, 6-2, 6-2 win over Gael Monfils. Also advancing was Juan Martin del Potro of Argentina, who ended the run of Kei Nishikori, the first Japanese man to reach the US Open's fourth round in the 40-year Open era. Del Potro won the contest between teenagers 6-3, 6-4, 6-3 for his 23rd consecutive victory. Del Potro will face Andy Murray of Britain, who beat Switzerland's Stanislas Wawrinka 6-1, 6-3, 6-3 in one hour 49 minutes in the final game of yesterday's play.

Venus and Serena Williams set up yet another Grand Slam family reunion. Two months after meeting in the Wimbledon final, this time they square off in the quarter-finals. Venus beat the ninth-seeded Agnieszka Radwanska of Poland 6-1, 6-3, and Serena dispatched wild card Severine Bremond of France 6-2, 6-2. Both sisters are two-time former US Open champions. They are 8-8 overall against each other, including 5-5 at majors.

Their matchups, however, usually come much later than the quarters. "I mean, it's tough to play her because she's so good," Venus said. "We're going stronger than ever, in my opinion." Also, sixth-seeded Dinara Safina beat qualifier Anna-Lena Groenefeld of Germany 7-5, 6-0, and will face No. 16 Flavia Pennetta, who defeated two-time major champion Amelie Maursemo 6-3, 6-0. Ranked 55th, Querrey gave a solid show and became the first player to take a set from Nadal at this Open.

His fans in the Arthur Ashe Stadium private box were vocal, particularly the three who had their shirts off and spelt out S-A-M on their chests. Querrey boomed 20 aces and showed no fear, trading big shots with Nadal all match long. He drew a standing ovation at the end for his effort, and smiled broadly. "Came up a little short. The guy's too good," Querrey said. Playing in his ninth US Open and coming off his upset over James Blake, Fish kept busy as his wedding approaches. He will marry "Deal or No Deal" model Stacey Gardner on Sept 28 - she watched from his private box, minus her shiny No. 2 briefcase. "I desperately wanted to play well here," he said. "Desperately."

Fish matched the best Grand Slam result of his career, having reached the quarters at the 2007 Australian Open. Ranked as high as No. 17 in 2004, the 26-year-old Fish has worked three years to recover from an injured wrist that required extensive surgery. Fish waved to his private box after match point. The entourage included his father, Tom, who celebrated his birthday. No such fun for Monfils, who turned 22 yesterday. Safina coasted home after a close first set against Groenefeld, the first qualifier to reach the fourth round since Anna Kournikova in 1996.

Safina equalled her best result at Flushing Meadows, and kept up the best season of her career. Safina reached the final at the French Open and later won 15 straight matches before losing to Elena Dementieva in the gold-medal match at the Olympics. *AP