There is probably no one in tennis who polarises opinion more than the volatile Australian Nick Kyrgios.
He has certainly been making his presence felt at Wimbledon.
After Rafael Nadal pulled out of yesterday's semi-final match against Kyrgios with an injury, the 27-year-old suddenly finds himself in his first Grand Slam final.
For some, Kyrgios is a disagreeable, explosive character lacking respect for the game with his on-court antics designed to distract his opponents.
For those who value sportsmanship, he is a bit hard to take.
Others see him as an entertainer and a welcome free spirit who thumbs his nose up at officialdom and conventional behaviour.
His biggest asset is that underneath the circus act he is a very talented player with the most blistering serve in the business.
That is apart from the occasional underarm effort which, though perfectly legitimate, really annoys opponents.
If only he could drop the rants and just let his tennis do the talking.
One thing for sure is that he his box office as witnessed by the large, noisy crowds attending his matches at Wimbledon.
Interestingly in his fiery encounter with Stefanos Tsitsipas, the majority of the crowd were supporting Kyrgios, especially the younger fans.
This could be bit of a worry for parents who would be unlikely to rank Kyrgios top of the list of preferred role models.
The Australian's game plan against Tsitsipas was clearly to irritate his opponent and it worked a treat.
From the moment the Greek lost his cool, there was only going to be one winner.
To Kyrgios' credit, in his following matches he has been on his best behaviour, although he still had time for occasional rants. More importantly his tennis has been excellent.
Kyrgios is of course not the first tennis player to be accused of misbehaviour on court.
It is understandable that players will lose their tempers when things are not going well.
The red mist suddenly comes down, usually in the form of smashing racquet or shouting obscenities.
In one bizarre incident at Wimbledon 2012, Argentine player David Nalbandian gave foot-fault a new meaning when in anger he kicked an advertising sign which hit a line judge on the leg, drawing blood from the unfortunate official's shin.
Nalbandian was defaulted but was quick to apologise and later said he was "ashamed."
Line judges have traditionally been the targets of player abuse although the modern technology enabling players to challenge calls has improved matters considerably.
However, few will forget the US Open in 2009 when Serena Williams erupted at a female line judge who had the temerity to foot-fault the star on a vital point.
It was not one of Serena's finest moments.
Probably the most unlikely player to be involved in a controversy was England's Tim Henman at Wimbledon back in 1995.
The mild-mannered Henman lost his temper after missing a shot in a doubles match.
He whacked the ball in disgust but to his horror saw it slam into a ball girl's head, temporarily flooring her.
Henman and his partner were promptly defaulted, the first time this had happened at Wimbledon.
The English star was extremely apologetic and the next day there was a hastily arranged public relations exercise in which Henman presented the girl with a bouquet and gave her a big kiss.
Judging from the expression on the girl's face, she found the kissing far more terrifying than being whacked on the head.
We must not forget John McEnroe who in his time abused the crowd, line judges and most of all umpires.
At Wimbledon in 1981, McEnroe famously ranted at the umpire "You cannot be serious!"
His regular clashes with umpires became quite embarrassing and prompted the late Australian broadcaster Clive James to refer to him as "charming as a dead mouse in a loaf of bread."
McEnroe did, however, once display a sense of humour.
When the first electronic line judge Cyclops was introduced in 1989, McEnroe felt he was the victim of bad calls by the machine.
He stood there glaring at the umpire and blurted out "I think that machine knows who I am."