US boxer Floyd Mayweather Jr has been jailed for 90 days by a Las Vegas court after pleading guilty to assaulting his ex-girlfriend, Josie Harris, in 2010.
He was also ordered to pay a fine of $2,500 (£1,600) and complete 100 hours of community service.
Mayweather, 34, agreed to a plea deal, meaning he will not have to answer felony charges of beating Ms Harris and threatening two of their children.
Prosecutors said Mayweather's history meant jail time was appropriate.
"He just continually gets himself into trouble and he is able to get himself out of it as well," Prosecutor Lisa Luzaich told Judge Melissa Saragosa.
"Essentially it is because he is who he is and is able to get away with everything. The only thing that's going to get this man's attention is incarceration."
The judge said she decided to jail Mayweather after he admitted hitting Ms Harris and twisting her arm. Ms Saragosa, citing a police report, said that two of the former couple's children, ages 9 and 10, also witnessed the attack, in which Mayweather threatened to make Ms Harris "disappear".
Mayweather has been told to report to jail on 6 January 2012.
He is facing another court appearance next week on charges of assaulting a security guard outside his home in November 2010 in an argument over parking tickets. He is expected to plead no contest.
Ms Luzaich cited previous assault arrests, two in which Mayweather either paid fines or was required to complete community service, saying fines were of no consequence to the boxer.
Mayweather earned $25m for the fight than won him a World Boxing Council welterweight belt.
His lawyer, Karen Winckler, called Mayweather "a champion in many areas", including buying toys for children at Christmas and promising to donate $100,000 to breast cancer research by the end of the year.
Ms Winckler argued that a full community service sentence would be more productive.
His jail sentence means he will be released only two months before a major fight, likely to be against the Philippines' Manny Pacquiao, scheduled to take place on 5 May.