WHO, WHAT, WHY?
The Magazine answers...
The outburst by Serena Williams at the US Open was not the first time a tennis player has let off steam on court. So why all the tantrums?
When Serena Williams was dubiously penalised for a foot-fault when two points away from defeat, she could contain herself no longer.
Tennis tantrums are nothing new
She twice unleashed a tirade at the lineswoman and match officials intervened to award a point to her opponent, Kim Clijsters, effectively handing her the match and a place in the US Open final.
Earlier, Williams had been reprimanded for smashing her racket on the court.
In a sport where ill temper reached its apogee in the early 1980s antics of John McEnroe - why do there seem to be so many outbursts?
Former top British player Andrew Castle says that due to the intensity of the game, all tennis players suffer from bursts of anger that they ultimately have to keep under control.
"Most tennis players are just like any fit, young, wound-up people. But controlling your emotions is what training is about, what being a professional is about."
Castle says he had been prone to the occasional outburst himself.
"I had a bad temper. I was the most fined player in the world one year," he jokes.
But whatever minor outbursts cropped up in tennis, there are other sports with far worse offenders.
"Some of the worst things I've seen have come recently in the football Premier League. It's just appalling."
In football, players shout at the referee persistently, although using foul language in this way would usually bring a booking.
"Any sport is a pressure cooker and I don't think tennis is unique in that," says sport psychologist Craig Mahoney of Northumbria University, who worked for the Lawn Tennis Association for seven years.
But there are factors that contribute to its intensity, he says. The most obvious is that it's an individual sport and therefore there's no-one else to absorb the pressure.
Footballers lose their rag too
"In team sports, you see situations where other players come and pull a team-mate away but in tennis and squash you are dealing with your own mentality and ability to cope with the situations and that won't always be secure."
Another factor is the close proximity of the crowd. The US Open Centre Court is very imposing and is one of the most steeply banked in the world, so it's like a cauldron, he says.
Then there is the repeated - and inconsistent - intervention of officials, says Mr Mahoney, although technology has reduced their role in recent years.
"It's interesting how you might find someone is making a particular call in a certain position that doesn't happen at the other end. So there's an inconsistency that doesn't happen in many sports."
Controlled aggression can benefit a tennis player, he says, because anger, frustration and outbursts can raise one's emotional state and help get one's mind hyper-active. So clenched fists, shouting and shirt-tugging are deliberate techniques to this end.
But there are risks. This "hyper-arousal" worked for McEnroe in his early career but against him towards the end, when he was unable to control it, says Mr Mahoney.
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Some players like Roger Federer display little emotion on the outside, because all individuals have different levels of optimum arousal, and players like him know how to get there.
Squash players also have a tendency to blow up - smashing rackets and outbursts - because they have to deal with the added dimension of sharing personal space in a non-contact sport, he says.
"All sports have differences in mental, physical and technical requirements. Football seems to have fewer mental demands, while golf is physically less demanding.
"Most golf players are particularly unfit - Tiger Woods is an exception - and wouldn't run 100 metres very fast. The demand set in golf is very much about mental stability and technical efficiency."
Aggression in golf would work against performance because it would only raise the heartbeat excessively and cause an unsteady hand.