Floyd Mayweather Jr. turned himself in Friday and will begin serving a three-month jail sentence for attacking his ex-girlfriend in September 2010.

The boxing star appeared today at the Regional Justice Center in Las Vegas with a gray sweatsuit and sneakers. He was also sentenced to 100 hours of community service, a $2,500 fine and 12 months in a domestic violence treatment program.

""He'll be all right," Mayweather's friend, rapper 50 Cent, told reporters outside the courthouse, AP reports.

Mayweather pleaded guilty in December to pulling the hair and twisting the arm of his ex-girlfriend while two of their children were watching.

The guilty plea allowed him to avoid a trial on felony charges that could have sent him to prison up to 34 years if convicted.

Justice of the Peace Melissa Saragosa had allowed him to remain free long enough to hold a fight on May 5.

According to AP, Mayweather will have a small solo cell and will be away from other prisoners.

Mayweather is a five-division world champion, where he has won eight world titles, as well as the Lineal Championship in three different weight classes.

He is a two-time The Ring "Fighter of the Year," winning the award in and also won the Boxing Writers Association of America (BWAA) "Fighter of the Year" award in 2007 and Best Fighter ESPY Award 2007, 2008 and 2010.

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