Officials talk to Serena Williams (right) following her outburst
Serena Williams has issued an apology after the outburst towards a line judge which resulted in her losing her US Open semi-final against Kim Clijsters.
Williams said she wanted to "sincerely apologise" and added: "I need to make it clear to all young people that I handled myself inappropriately.
"It's not the way to act - win or lose, good call or bad call in any sport, in any manner."
The tirade cost her a $10,000 (£6,000) fine and followed a foot-fault call.
Williams' initial statement after the incident did not contain a straight apology, although she admitted that her "passion and emotion" had got the better of her, and said she had "handled the situation poorly".
Williams said: "I want to amend my press statement, and want to make it clear as possible.
"I want to sincerely apologise first to the lineswoman, Kim Clijsters, the US Tennis Association, and tennis fans everywhere for my inappropriate outburst.
"I'm a woman of great pride, faith and integrity, and I admit when I'm wrong."
The controversial call handed eventual champion Clijsters match point.
I will learn and grow from this, and be a better person as a result
As the Belgian wild-card entry waited to play the next point, Williams, who had already been handed a code violation for racquet abuse, vented her frustration.
She unleashed a tirade towards the line judge, briefly walked away and then returned for another blast at the official.
Chair umpire Louise Engzell then intervened, asking the line judge what had been said, while tournament referee Brian Earley was also summoned.
The officials eventually ordered a point penalty, the next level of punishment after an initial code violation, which gave the match to Clijsters.
Williams said: "I like to lead by example. We all learn from experiences, both good and bad. I will learn and grow from this, and be a better person as a result."
The 11-time Grand Slam champion has been fined $10,000, and further penalised $500 for racquet abuse in the same match.
WTA Tour chief Stacey Allaster called the 28-year-old's conduct "inappropriate and unprofessional".
Allaster's statement continued: "No matter what the circumstances, no player should be allowed to engage in such behaviour without suffering consequences.
"Serena is a great player who has done so much for our sport, and I am certain she will continue to be a role model to millions of young women who want to play the game and excel as Serena has done.
"As a role model, it's important for a leader like Serena to step forward and recognise her behaviour last night was unacceptable."
The Grand Slam committee administrator has opened an investigation to determine whether Williams' behaviour should be considered a "major offence".
Williams had been unrepentant about the incident in her post-match press conference, claiming to not remember what she had said to the line judge and saying her actions were not unprecedented.
She was later seen entering referee Earley's office before leaving the Billie Jean King National Tennis Centre.
Serena explains outburst
According to the Grand Slam Rule Book, unsportsmanlike conduct when referred to the Grand Slam committee can be treated as "aggravated behaviour", which "is flagrant and particularly injurious to the success of a Grand Slam, or is singularly egregious".
The rule book states that such a violation "shall subject a player to a fine of up to $250,000 or the amount of prize money won at the tournament, whichever is greater".
It also states that a player can be permanently suspended from play in all Grand Slams and/or the Tennis Masters Cup if found guilty.
Williams, who was beaten 6-4 7-5 by Clijsters, earned $350,000 in prize money for reaching the final four.
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