John Terry was goaded about an alleged affair before throwing a racist insult at Anton Ferdinand, a court heard.
Chelsea and England defender Terry, 31, is accused of calling Ferdinand a 'f****** black c***' during a Premier League match last year.
Appearing at Westminster Magistrates' Court on Monday, Terry sat in the dock wearing a light grey suit, white shirt and pink tie.
The court heard that Terry told Queens Park Rangers player Ferdinand to 'f*** off' and also called him a 'f****** knobhead' as the pair exchanged insults.
Opening the prosecution on Monday,
He went on: "The Crown's case is that the words were abusive and insulting in a straightforward sense and that the term 'f****** black c***' was uttered as an abusive insult demonstrating hostility based on Mr Ferdinand's membership of a racial group."
Terry maintains he was only sarcastically repeating words that Ferdinand wrongly thought he had used.
He is accused of a racially aggravated public order offence, which he denies.
Chelsea was down to nine men in the clash at Loftus Road, when Ferdinand and Terry began trading insults over a penalty claim, the court heard.
Giving evidence on Monday, Ferdinand said: "He called me a c*** and I called him a c*** back and he gave me a gesture as if to say my breath smelled.
"I said to him, 'How can you call me a c***? You shagged your team-mate's missus, you're a c***'."
This was a reference to Terry's alleged affair with
Ferdinand jogged down the pitch making a fist gesture to imply sex, he told the court.
At first QPR centre-half Ferdinand did not think any racist insult had been used.
He shook hands with Terry and accepted that their clash was 'handbags' and 'banter'.
But after the match, his then girlfriend showed him a clip of their exchange posted on YouTube, and he believed Terry had used the racist obscenity.
Ferdinand told the court that if he had realised at the time he would have told officials.
He said: "I would have been obviously very hurt and I probably wouldn't have reacted at the time because, being a professional, you can't do that. I probably would have let the officials know what happened and dealt with it after the game.
"When someone brings your colour into it, it takes it to another level and it's very hurtful."
Terry met with Ferdinand after the match to ask what had happened.
"Mr Terry said, 'Do you think I racially abused you?'. I was like. 'No'," Ferdinand told the court.
"I said 'No, that never came out of my mouth'. Then
Mr Carter-Stephenson claimed Ferdinand's agent
He alleged Ferdinand only decided to go to the police when Mr Rigby persuaded him to, but the QPR player denied this.
The case is being heard by Chief Magistrate
Both television clips and unbroadcast footage of the incident, which would normally be used for training purposes, were shown to the court.
In a statement made to police last November, Terry said he was offended by the accusation that he had used racist language.
He said his words to the other player were meant to make it clear that he had not used a racist insult, and that Ferdinand was a 'knobhead' for thinking that he had.
The statement read: "Whilst footballers are used to industrial language, using racist terms is completely unacceptable whatever (the) situation.
"I was completely taken aback by this remark as I have never been accused of something like that and I did not take his remark lightly at all, and took strong offence to his suggestion."
The trial, expected to last five days, continues on Tuesday.