Zac Stacy will spend more time behind bars for attacking his ex-girlfriend on two separate occasions in 2021 ... the former NFL running back was just sentenced to six months in jail in the cases.
An Orange County, Fla. judge made the ruling in a courtroom on Monday evening, according to WESH 2 News ... also sentencing the 31-year-old to one year of probation.
Stacy had initially been accused of getting violent with the mother of his child, Kristin Evans, in mid-August 2021 -- when he allegedly flew into a violent rage over rent money.