Former welterweight titlist Victor Ortiz -- once also a "Dancing with the Stars" competitor -- has been charged with misdemeanor assault and battery for allegedly beating a guy up at a Jason Aldean/Kenny Chesney concert.
TMZ Sports broke the story ... the 28-year-old -- who has appeared in several movies including "Expendables" and "Southpaw" -- was originally arrested for assault with a deadly weapon on July 25th after a fight broke out at the Rose Bowl.
Ortiz and his brother allegedly got into it with another man -- and officials say Ortiz kicked the man while was down.
The L.A. County District Attorney declined to press felony charges -- and kicked it down to the Pasadena City Prosecutor who decided to move forward with misdemeanor charges.
Ortiz was hit with assault and battery. If convicted, he faces up to 1 year in jail for each charge.
Victor's brother was charged with one count of battery causing serious bodily injury.
Ortiz is set to be arraigned next week.