Dundee United and St Johnstone fans are facing cup final train travel chaos because Network Rail are closing the track for maintenance on the day.
There will be no direct trains from Dundee and Perth to Glasgow on May 17 because of the replacement of the railway bridge at Larbert.
Trains will instead be re-routed through Fife to the Forth Bridge.
This could add at least half an hour to the journey but the precise effects of the disruption are not yet known.
Network Rail apologised for the inconvenience but said the track upgrade work has been planned for two years and cannot be put off because Dundee United and St Johnstone are in the cup final.
Train operators ScotRail were planning to run replacement buses round the obstruction between Stirling and Glasgow before the teams playing in the William Hill Scottish Cup final at Celtic Park were known.
A ScotRail spokesman said: “Following the results of the weekend’s cup games, we are contacting the clubs to discuss how we can help Dundee United and St Johnstone football fans travel to and from Glasgow.”
Fans of both sides were expecting news of extra direct trains to the historic all-Tayside climax of the Scottish football season at Celtic’s 60,000-capacity stadium next month.