Authorities in Victoria are on high alert ahead of this weekend's Grand Final even though there's no increase in the threat level for the clash between the Western Bulldogs and Sydney Swans.

"No threats have been made in relation to infrastructure or these events," Victoria Police Minister Lisa Neville told AAP on Wednesday.

But a massive police presence will target anti-social behaviour, with additional officers patrolling car parks and train stations for Saturday's match at the MCG before an expected crowd of 100,000.

Earlier this month Victoria Police insisted it was safe for fans to attend the AFL finals despite Islamic State calling on followers to commit lone-wolf attacks at the MCG.