A 37-YEAR-OLD Adelaide man is to face court over an altercation during last Saturday night's Showdown between Port Adelaide and Adelaide.

The man has been reported for affray and assault after allegedly punching another man from behind during a crowd brawl after the final siren at Adelaide Oval.

He will be summonsed to appear in Adelaide Magistrates Court at a later date and has also been issued with a three-month order barring him from the oval, police say.