Mystery surrounds why part of the city's London Road suddenly fell apart and what caused a sewer pipe under the busy thoroughfare to burst.
Council inspectors and Scottish Water officials launched an investigation into the collapse – but still do not know why this latest problem occurred.
It is the second time this year the road has been closed. It reopened in June after being shut for five months because of a dangerous building.
Today council bosses said it would take "several months" before the road was fully re-opened, after the collapse on October 18.
A Glasgow City Council spokesman said: "Specialist engineers are investigating what caused damage to the road structure, a waste water pipe and other utility services.
"They will also assess what work will be required to resolve the problem permanently.
"It is likely that work will take several months and, for safety reasons, traffic management will continue to be required.
"However, every effort will be made to minimise disruption to road users."
London Road, from its junction with Springfield Road to the Clyde Gateway junction, which takes in Celtic Park, has been closed to through traffic to allow work on the problem.
There is access to the stadium, but drivers have been warned to prepare for congestion on the Gallowgate diversion route.
A Bridgeton resident said: "This is a nightmare us, just months after the road was finally re-opened after the tenement collapse.
"Not only will it be a big inconvenience for getting around, but the impact on local businesses doesn't bear thinking about. I hope the council gets the work done in double-quick time.
"This part of the East End has already put up with enough."
A statement from Scottish Water said: "Glasgow City Council, Scottish Water and other relevant parties have completed initial investig-ations into what caused damage to the road structure, a waste water pipe and other utility services in part of London Road and to assess what repair work is required.
"However, it has been agreed by all relevant parties involved that, due to the complex nature of infrastr-ucture, further investigations are required by specialist engineers, before the cause can be established and a permanent solution found.
"Glasgow City Council, Scottish Water and the other relevant parties apologise for the inconvenience caused."
The road was closed earlier this year after cracks in a tenement, near Bridgeton Cross, meant it had to be demolished.
Road subsidence is the latest inconvenience for city road users, as reported this week in the Evening Times.
We told how holes have suddenly appeared in Waterloo Street, Renfrew Street and Renfield Street.