King is said to have groped the woman and made repeated advances on her at the Soho Revue bar last December. She asked him to stop pestering her, and told King to "take your multi-millions and leave".
In response King is alleged to have said: "you're not even in my league" and then allegedly "smashed her in the face with a clenched fist".
Marlon King: Facing charges of sexual assault and actual bodily harm
The trial is taking place at Southwark Crown Court and Roger Daniells-Smith, prosecuting, said King touched the 20-year-old on the bottom in a "deliberate and sexual" way before the act of "completely gratuitous violence" just minutes later.
The victim told the court she was "quite disgusted and shocked" and said she turned to see the man "smirking at me in a suggestive way". She said "firmly" to him: Don't touch me."
Rather than "taking the hint", King allegedly turned to two other women in the group who also "recoiled from his touching them and told him very clearly to stop behaving in this manner," Mr Daniells-Smith said.
King is said to have continued to harass the group and when the first woman told him to stop again he replied: "Don't you know who I am, I'm a millionaire".
"Then he started poking me in the head, pushing my temple like he was enjoying it, repeating 'not even in my league'," the woman told the court, "I kept on repeating 'take your multi-millions and leave - no one cares, just get away from the table. I felt tiny, I felt really embarrassed."
She said that when she tried to "shoo" him away, he grabbed her wrist and pulled it down, then when a friend intervened, let her go.
It is the alleged that the woman made an attmept to "shoo" King away. The striker is then said to have grabbed the woman's wrist. "When I looked up he punched me in the face," the woman said. "It was hard enough to knock me off my feet."
"It split my lip, broke my nose and gave me a black eye. It felt like I was bleeding everywhere but it was mainly my nose and mouth."
King denies both sexual assault and causing the woman actual bodily harm, insisting that he is the victim of mistaken identity.
In response, Mr Daniells-Smith said that "many witness" saw King both attack the woman and immediately recognised him as a "high profile sportsman."
The trial continues today.
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