One of the city's busiest train lines could be re-routed as part of the Melbourne Metro Rail project, leaving thousands of passengers without a direct service to South Yarra and Richmond stations.



As the Andrews government starts planning how trains will use the new tunnel, one option is for the Cranbourne-Pakenham services to skip South Yarra and Richmond and travel directly from Hawksburn to Domain, one of the five underground stations that will be built as part of $11 billion project.

If adopted, the realignment is likely to prove contentious given the number of people who use the two interchanges to get to work or sporting venues such as the MCG.

South Yarra Station, which could be bypassed by the new Metro rail tunnel.

On one hand, it would require many commuters to find an alternative train service to reach their destinations, but, on the other, it could also free up some space at the ageing South Yarra Station, which users say is already stretched and in desperate need of refurbishment.

Stonnington Mayor Melina Sehr said she was not aware of the proposal to redirect the Cranbourne-Pakenham train lines, but added that bypassing South Yarra seemed "bizarre" given the extraordinary growth of residents who would require more trains to stop at the station in coming years, not less.