Coaches are replacing V/Line trains on the Geelong Line between Lara and Wyndham Vale, due to a track fault at Little River.
Express shuttles are also operating between Lara and Werribee, where passengers can catch a Metro Trains service to Southern Cross Station.
PTV ask passengers to check station platform displays and listen for announcements, and to allow additional time for their travel.
Train services will continue to operate between Southern Cross Station and Wyndham Vale.
PTV asks motorists to be vigilant for extra coaches and pedestrians around stations along the Geelong Line.
Services will resume when repairs have been completed.
Real-time traffic conditions are available at traffic.transport.vic.gov.au. The latest public transport information and network status is available at ptv.vic.gov.au or in the PTV mobile app.
