Roadworks that closed Heatherton Road are behind schedule.
The Noble Park thoroughfare was due to reopen on Monday 18 June following works to remove railway tracks and asphalt the road surface.
But VicRoads is advising that it will remain closed at the train line in both directions until Thursday 21 June.
Signed detours will be in place along Corrigan, Chandler, Kelvinside and Lightwood roads and Douglas Street.
VicRoads said delays were expected and drivers should avoid the area if possible.
Real time travel advice is available at traffic.vicroads.vic.gov.au.