A MAN has died after allegedly being knocked unconscious following a local football match in the state's southwest.

Paramedics were called to the Heywood Recreation Reserve on Edgar St about 5.25pm following reports of an alleged assault.

Ambulance Victoria spokesman John Mullen said the man, aged in his 40s, went into cardiac arrest after he was knocked down.

Mr Mullen said bystanders performed CPR on the man before paramedics arrived and took over.

But the man could not be resuscitated and died at the scene.

Detectives from Hamilton are investigating the alleged assault, which occurred after a South West District Football League match between Heywood Football Club and Westerns Football Club.

The Sunday Herald Sun understands the victim was a spectator at the match, supporting the local side.

The exact circumstances surrounding his death are yet to be determined.

Police are yet to arrest anyone over the alleged attack.

Heywood FC would not comment on the incident, but said it would release a statement on Sunday.

Westerns FC senior vice-president Peter Keem said he and his players had "well and truly" left the ground before the incident occurred.

A local cafe worker said the man's death was "devastating for the community".

It comes just a week after Otway Districts Football Club captain Aaron Mahoney, 24, died after collapsing on field at Gellibrand Recreation Reserve.

Anyone with information should contact Crime Stoppers on 1800 333 000.

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