Rafael Nadal was stunned by Fernando Verdasco in the last 16 of the Madrid Open - and then threatened to skip next year's event unless the blue clay is dug up.
Verdasco triumphed 6-3 3-6 7-5 in the pair's last-16 clash to end Nadal's 22-match winning streak on clay, one stretching back almost a year when Novak Djokovic beat him in Rome.
It was the first time Verdasco had ever beaten his Spanish compatriot in 14 attempts.
However, the drama in the Spanish captial continued in the press conference room with Nadal saying he was prepared to skip his home event in 2013.
"Movement is very important for me and I couldn't move," he said, referring to the slippery nature of the new blue clay which has irked many players this week.
"I couldn't hit ball the way I wanted. I lost because I deserved to lose."
He added: "The ATP and the tournament can do what they want, I tried my best, I've trained here since Thursday. I was as prepared as I could be.
"I was not good enough to adapt my game to this court. If things continue like this, it will be very sad.
"If things don't change, this will be one less tournament on the calendar for me."
In their six previous claycourt matches, Verdasco had not even won a set but he soon put that staistic to bed by claiming a lengthy first set on the controversial surface which again had both men sliding around.
However, despite clearly being well below his best, Nadal showed his renowned fighting qualities to hit back in the second and square the match.
The second seed appeared well set for victory when he eased into 5-2 lead in the decider with a double break of his opponent's serve.
However, twice he failed to serve out, producing a string of uncharacteristic errors, none more cringeworthy than a smash into the net which would have brought him within two points of victory at 5-2.
Verdasco, handed a lifeline, took full advantage.
Having won five straight games he earned match point on Nadal's serve at 5-6 only for the door to be slammed shut with an ace.
However, a second chance soon followed and when Verdasco punished a short ball with a forehand winner he claimed the win and collapsed to the court in delight.
Novak Djokovic and Roger Federer had no such problems, both winning in straight sets.
Djokovic, a heavy critic of the surface after struggling to victory in his opener, beat Stanislas Wawrinka 7-6 (7/5) 6-4 in the evening session.
Asked about the blue clay again after his latest win, Djokovic said he agreed with Nadal's boycott threat and predicted this week's winner would be "the one who doesn't get hurt".
The top seed, who next meets Janko Tipsarevic, remains on course for a semi-final clash with Federer. Seventh seed Tipsarevic came through a three-set battle against Frenchman Gilles Simon 7-6 (7/3) 5-7 6-1, while Federer raced to a 6-3 6-2 victory over Richard Gasquet - in stark contrast to his final-set tie-break win over Milos Raonic on Wednesday night.
The third seed will next meet David Ferrer, who was kept on court considerably longer by fellow Spaniard Nicolas Almagro before claiming a 7-6 (7-5) 3-6 7-6 (10-8). Ferrer saved three match points befre clinching his place in th last eight.
Their match also saw the blue clay come in for criticism, Almagro bashing the balls in frustration as the umpire was called off his chair to inspect the court.
Earlier, fourth seed Jo-Wilfried Tsonga had lost to leave the bottom half of the draw - the section initially featuring Nadal - wide open.
Tsonga suffered a narrow 7-5 3-6 7-6 (7/2) defeat to Ukraine's Alexandr Dolgopolov.
Sixth seed Tomas Berdych is now the highest ranked player in the section. He was an easy 6-1 6-1 winner over Gael Monfils, of France. He will now meet Verdasco.
Juan Martin Del Potro will also be fancying his chances now.
Last week's winner in Estoril progressed to the quarter-finals, where he will meet Dolgopolov, by easing past Marin Cilic 6-2 6-4.