Authorities say 24-year-old Adrian Roberts was discovered lying on Jefferson Avenue in Brentwood around 11 p.m. He was pronounced dead at the scene.
Now, investigators are trying to figure out what caused his death and if it was a hit-and-run accident.
The medical examiner will perform an autopsy to determine the cause of death.
Anyone who may have witnessed what happened is asked to call Crime Stoppers at 1-800-220-TIPS.