Metro Trains has warned of delays up to 15 minutes on the Werribee, Williamstown, Pakenham, Frankston and Cranbourne lines due to the scooter on the tracks.

The Metropolitan Fire Brigade received a call about 5pm to assist Ambulance Victoria with a man whose mobility scooter had driven off platform eight.

A high-angle rescue team was dispatched to help lift the scooter from the tracks.

Crews managed to rescue the man and retrieve the scooter just after 6pm. He was taken to The Alfred hospital with minor injuries.

Metro closed the platform and diverted services.

As of 7pm, Metro was still warning of 10-minute delays on the Cranbourne and Pakenham lines.

It is unclear what caused the accident but commuters have described parts of platform eight as narrow and cramped in the wake of the news.

On Twitter, Public Transport Users Association Daniel Bowen said the east end of platform eight was "very narrow".

Another commuter agreed, writing: "Just got on at platform eight and thought how cramped it was at east end".