David Tennant was said to be "gutted" at being forced to pull out of his sell-out Hamlet role due to a bad back.
The actor missed Monday night's performance at London's Novello Theatre and the Royal Shakespeare Company confirmed he was too unwell to play the part tonight (Tuesday), to which members of the press were invited.
It's understood the Doctor Who star's problem is a long-standing one.
Edward Bennett, who normally plays Laertes, played Hamlet last night and received a standing ovation, the RSC said. The show will go on in David's absence, with Bennett in the title role.
RSC chief associate director Gregory Doran said: "David is gutted, not only at the thought of disappointing audiences, but also to be unable to perform a role that he's worked on and developed throughout 60 performances in Stratford-upon-Avon.
"Before this injury, he has only ever been off for one performance in his entire career to date, and is hoping that he will be able to return to the show as quickly as possible."
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.