David Tennant had to pull out of his sell-out role as Hamlet due to a bad back, the Royal Shakespeare Company (RSC) said today.
The actor was forced to miss last night's performance at London's Novello Theatre and the RSC is waiting to find out if he will be able to perform tonight.
It is understood that the Doctor Who star's problem is a long-standing one.
An RSC spokeswoman said Edward Bennett, who normally plays Laertes in the production, played Hamlet in Tennant's absence last night.
She said he received a standing ovation.
The production has been one of the hottest theatre tickets of the year.
Seats for the London performances were snapped up within a few hours as queues snaked round the building.
But Tennant's back trouble is not the first problem to have beset the hugely popular show since its move to London.
It transferred from Stratford-upon-Avon to the West End last Wednesday - and the RSC confirmed last week that it had been targeted by counterfeiters.
Organisers were alerted after some sophisticated-looking copies of tickets were presented at the Novello's box office last month.
They were forgeries of those issued by Delfont Mackintosh Theatres (DMT), which runs the theatre, and tickets were being re-issued to avoid chaos.
The RSC said a counterfeiting incident such as this had not happened to the company before.
Tonight also happens to be the night that members of the London press have been invited to see the event.
Tennant will be standing down from his Doctor Who role and his successor is yet to be confirmed.
He will return to TV screens as the Doctor over Christmas.Reuse content