Nadal's quirks in spotlight

A psychologist has urged TV commentators and fans to stop mocking Rafael Nadal's repetitive mid-match "routines" because the world No 1 might be showing signs of obsessive-compulsive behavior.

Christopher Mogan complained to broadcaster Channel Seven after coverage focused on Nadal's habits, which include lining up his water bottles with the labels facing a certain way.

"What upset me is that I think it's known that Rafa has obsessive-compulsive indications," he told The Age newspaper.

"Two to three percent of people have this seriously disabling condition and they would be identifying with him when he does his square walk, how he places his bottles in a row, very carefully.

"They are routines, but the point is they are meant to try to control anxiety. It's about getting a 'just right' feeling: 'I can feel just right if I line my bottles up.'."

The 13-time Grand Slam-winner goes through an identical routine before every serve, involving pulling at the back of his shorts and touching each shoulder, both ears and his nose.

He also refuses to step on lines between points, and Lleyton Hewitt told a story during the Channel Seven coverage about how Nadal takes his shirt on and off repeatedly before leaving the locker room.

"It's being highlighted, and it's disrespectful to him," Mogan said. "Obsessive-compulsive disorder sufferers would be very distressed by that, that they were being laughed at, basically.

"(OCD) is a mental illness, one of the most common anxiety disorders."

According to The Age, a member of Nadal's camp dismissed any concerns and his coach has said the behavior is merely superstition.

He is not the only player with repetitive routines. Maria Sharapova goes to the back of the court and stares intently at her racket between points, and Andy Murray wipes his face with a towel.

Mogan, who said he could not diagnoze Nadal without speaking to him, also acknowledged he could be displaying "perfectly controlled behavior that belongs only on the tennis court".

"It is possible it could be just a manifestation of the control athletes seek to get," he said.