Michael Montgomery, 21, of Lodi was free Saturday after the San Francisco County District Attorney's office said it was not yet ready to file charges in the stabbing death of Jonathan Denver, a 24-year-old Los Angeles Dodgers fan killed in a sidewalk altercation blocks from AT&T Field after Wednesday' people's burden to prove beyond a reasonable doubt that the defendant did not act in lawful self-defense," the district attorney's office said in a written statement late Friday.
The statement asked anyone who "witnessed the incident or has video" to contact police, CNN said.
Montgomery's father told the San Francisco Chronicle Friday authorities had no grounds to charge his son because he was defending himself and drew a knife only after being hit with a chair.
Police have said the altercation began while fans were filling up pubs around the ballpark following the Giants' game against the downstate rival Dodgers.
Montgomery and his friends, who were Giants fans, exchanged words with the victim, who was with his brother and father. The situation deteriorated and Denver was fatally stabbed.
The Chronicle said Montgomery was treated at a hospital for injuries suffered in the fight.