Rafael Nadal calls them his ''routines'', but a psychologist who specialises in obsessive-compulsive disorder has warned against trivialising or even mocking the Spaniard's habitual on-court behaviours, fearful of the distress it could cause sufferers of the disabling mental illness.
Dr Christopher Mogan was so outraged by commentary from Jim Courier and Lleyton Hewitt during Nadal's third-round match against Gael Monfils that he contacted Channel Seven to complain.
It is possible it could be just a manifestation of the control athletes seek to get.
He said it was impossible to diagnose somebody without speaking to them, but felt the world No.1 ''seems to have a psychological disorder which is being ridiculed''.
Rafael Nadal takes a tumble during his fourth-round match against Kei Nishikori on Monday. Photo: Getty Images
''What upset me is that I think it's known that Rafa has obsessive-compulsive indications,'' Dr Mogan said. ''Two to 3 per cent 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're meant to try and control anxiety. It's about getting a 'just right' feeling: 'I can feel just right if I line my bottles up.' It brings a sense of completion, and if you leave something incomplete, it creates a stress.''
Dr Mogan felt Courier and Hewitt were ''overting'' Nadal's on-court tics, which include lining up water bottles with the labels facing the end he is about to play from, refusing to step on lines in between points, and running his thumb and finger down his nose before each point.
He believed the cameras highlighted the Spaniard's behaviour in a systematic manner he had not noticed at previous Australian Opens, and he was also disturbed by Hewitt relaying the story of Nadal putting his shirt on and taking it off over and over again before he left the locker room.
''It's being highlighted, and it's disrespectful to him. [OCD 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.''
A member of Nadal's camp dismissed Dr Mogan's concerns, describing Nadal as a normal guy with routines he believed helped his tennis. The spokesman said Nadal had great respect for Courier and Hewitt, and felt they always treated him well.
Dr Mogan said it was possible Nadal was displaying ''perfectly controlled behaviour that belongs only on the tennis court'', similar to batsmen in cricket tugging at their clothes or protective equipment in the same ordered, ritual fashion between deliveries.
''It is possible it could be just a manifestation of the control athletes seek to get,'' he said.
Asked if such behaviour by athletes generally translated into their everyday life, he said: ''To the extent that Rafa's got it, yes. There are people who have OCD and nobody knows they've got it.''
Nadal's uncle and coach, Toni Nadal, has spoken of his nephew's ''routines'', and his belief that anyone doing ''senseless things over and over'' amounted to being superstitious.
''He has told me before he can stop doing them and I have told him to do it,'' Toni Nadal said in 2012. ''It does not affect his game, but if he needed those things to play well, it would be bad.''
Former Australian professional and now Tennis Australia development manager Scott Draper revealed in a 2005 interview with the ABC's Australian Story that he had battled OCD early in his career, taking hours to get to bed as he moved around the room straightening objects and touching things in multiples of three.
In Nadal, he sees someone who is highly superstitious, but not to the point where it is a problem.
''I wouldn't say he's in the realm where if someone forced him to do something different he wouldn't be mentally strong enough to overcome that,'' said Draper, who wrote about OCD in his autobiography.
''I do understand there would be some people out there who are very fragile and they've got a problem they can't overcome, a debilitating thing, and they might look at that and think, 'He's got something similar to what I've got and someone's taking the piss, I resent that', Draper said.
''I get that as well. [But] when it comes to Rafa himself, I don't think he's suffering from a disorder.''
Dr Mogan was pleased the focus on Nadal's behaviour was not repeated in his fourth-round win, although a Channel Seven spokesman said no directive had been given to ignore his rituals. Nadal returns to court on Wednesday against Grigor Dimitrov.