Madrid: The promoter of the Mutua Madrid Open tennis tournament, Ion Tiriac, promised to make desired changes to the playing surface by the next edition after many players expressed displeasure about the playing surface.

Both World No.1 Novak Djokovic and No.2 Rafael Nadal threatened to boycott next year's edition due to the blue coloured clay used in the playing surface for the first time ever.

Along with other players, the pair had previously expressed their unhappiness over not being consulted players before changing the playing surface.

However, following his defeat to Fernando Verdasco Thursday, Nadal expressed his displeasure saying that Madrid would be one date less on his calendar unless the playing surface was changed.

Nadal explained that the blue clay was slippery, something that has been clear to see throughout the week, as well as commenting that the surface was of little use in helping him prepare for the clay-court of the Rome Masters and the French Open, which follow Madrid in the calendar.

In the face of the threat of losing the two main draws in the men's tournament, Tiriac said changes would be made for the 2013 edition of the Madrid Open.

"It's true it's slippery, but the clay won't be like this next year," he said, without specifying whether or not the organizers would improve the blue or return to the traditional red clay, which is used on the rest of the European clay-court circuits.

However, he made a call for Nadal and Djorkovic to be professional in their decision. "If Nadal and Djokovic don't come we will lament it and it will be sad, but I hope they are professional," he said.

"It is slippery and the hotter it is, the more slippery it gets," said Serena Williams about the blue court after her defeat to Maria Sharapova.

Women's world No.1 Victoria Azarenka expressed her dissent about the court and expected players will unite after the tournament to decide about the future of the tournament.

"It's not just one player who has complained about it and I can say I am not a fan of this court. It is very slippery and a lot of the time you feel unstable and I am certain that when the tournament is finished the players will get together to talk about it," she said. (IANS)