Chelsea and England defender John Terry racially abused rival footballer Anton Ferdinand in response to taunts about his alleged affair with a teammate's girlfriend, a court heard Monday.
Terry was charged with a racially aggravated public order offence following the emergence of video footage appearing to show him abusing Queens Park Rangers defender Ferdinand during a Premier League match last October.
The Chelsea captain, 31, allegedly used a racist slur against Ferdinand, who is mixed race, along with a string of obscenities as the pair traded insults, Westminster Magistrates' Court in London heard.
Lip-reader Susan Whitehood, assessing the footage of the incident, told the court that the video showed Terry using these words.
Terry maintains that he was only sarcastically repeating words that Ferdinand, who is mixed-race, wrongly thought he had said earlier.
"When someone brings your colour into it, it takes it to another level and it's very hurtful," Ferdinand, 27, told the court as Terry watched from the dock.
The QPR player said he did not initially believe that any racist terms had been used. He said he had shaken hands with Terry and accepted the verbal clashes as "banter".
But after the match, Ferdinand's then-girlfriend showed him a YouTube clip of the altercation which convinced him that Terry had used racist language, he told the court.
He added that if he had realised at the time what had been said, he "probably would have let the officials know what happened and dealt with it after the game."
Terry was allowed out of the dock to watch footage of the alleged racial abuse.
If found guilty, he could be fined up to £2,500 (3,150 euros, $3,850), although the damage to the Chelsea captain's lucrative commercial deals would likely be far greater.
Prosecutor Duncan Penny said Terry's words "demonstrated hostility based on Mr Ferdinand's membership or presumed membership of a racial group".
The insult was made "most probably in response to physical gestures being made by Mr Ferdinand which the defendant understood to refer to the well-publicised allegation of an extra-marital affair with a teammate's girlfriend," Penny said.
Allegations emerged in 2010 that Terry, who is married, had an affair with Vanessa Perroncel, the former girlfriend of his then England teammate Wayne Bridge.
Questioning Ferdinand, Terry's lawyer George Carter-Stephenson suggested that the QPR player made up the racist abuse claim after his jibe about Perroncel did not have "the desired effect" of winding Terry up.
Ferdinand denied inventing the allegation, though he admitted he had been trying to rile Terry as he was angry at the Chelsea captain for trying to get a penalty and because he "barged me in the back for no reason".
A few supporters outside shouted "Good luck, John!" to Terry as he arrived at court, wearing a grey suit and pink tie. He did not speak to reporters.
At an earlier hearing Terry's lawyers entered a not guilty plea on his behalf.
His trial was delayed until after the Euro 2012 championships after a judge heard that a number of other Chelsea players would be unable to appear as witnesses until the end of the football season.
Terry was stripped of the England captaincy by the English Football Association in February as a result of the racial abuse allegations. Fabio Capello resigned as England coach following that decision.
The case also caused friction when Terry was selected for the Euro 2012 squad last month but Manchester United defender Rio Ferdinand was left out.
Rio Ferdinand sent a message of support to his brother Anton on Monday, tweeting: "Head high bruv."
The trial is expected to last five days.