The players have labelled the new controversial court "too slippery" and only fit for "smurfs (to) play on".

After a shock 6-3 3-6 7-5 third-round defeat by fellow Spaniard Fernando Verdasco, the French Open champion vowed not to return to the Masters event unless traditional red courts, which are slower and more suited to his game, were reinstated.

"The movements are very important for me and here I cannot move so I cannot hit the ball the way that I want," he told a news conference after squandering a 5-2 lead in the final set.

"The ATP and the tournament can do what they want," he added referring to the controversial innovation sanctioned by the governing body of men's tennis for this year's tournament.

"I tried my best to prepare but I wasn't good enough to adapt my game to this court.

"The only thing that I know is that if things continue like this I am very sad but next year will be one less tournament in my calendar."

Nadal's outburst was perhaps unsurprising considering he would have fancied his chances of beating Verdasco, the 15th seed, having won all 13 of their previous meetings.

However, an error-strewn performance ended the world number two's bid for a third straight clay title this season and deprived him of a chance to avenge his defeat by Novak Djokovic in last year's final.

CLAY KISS

Verdasco's success was all the more astonishing given that Nadal twice failed to serve out the match in the deciding set.

Verdasco broke his Davis Cup team mate's serve seven times in all, losing his own six times, and clubbed 31 winners to his opponent's 19.

A typically crashing forehand drive sealed victory on his second match point and he fell flat on his back on the court before kissing the clay and heading off to play a doubles match.

"I lost because I deserved to lose today," Nadal said.

"Even when I was 5-2 ahead and I had a chance to close the match I didn't know how to do it. He played better than me and he beat me, that's it."

Verdasco next plays Czech sixth seed Tomas Berdych, who was the first player into the last eight when he thrashed 12th-seeded Frenchman Gael Monfils 6-1 6-1.

He was joined by Ukraine's Alexandr Dolgopolov, the 16th seed, who edged out French fourth seed Jo-Wilfried Tsonga 7-5 3-6 7-6.

Dolgopolov will play 10th seed and former U.S. Open champion Juan Martin Del Potro for a place in Saturday's semi-finals after the rangy Argentine thumped fellow big-server Marin Cilic of Croatia 6-2 6-4.

World number one Djokovic plays unseeded Swiss Stanislas Wawrinka later on Thursday, while Wawrinka's countryman, world number three Roger Federer, takes on 14th seed Richard Gasquet, another Frenchman.

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