Did you break a leg? No, but I dislocated a finger...

Simon Russell Beale and Jo Dockery in Shakespeare's Timon of Athens (Rex Features)

Breaking a leg on stage is meant to be an actor's worst nightmare but for Simon Russell Beale it was his finger that proved his undoing.

The award-winning actor slipped and fell during a particularly intense scene in Timon of Athens at the National Theatre on Wednesday night, bringing the show to a dramatic halt. Initially, the audience did not realise anything was wrong, as Beale carried on with his lines despite being in a great deal of pain. Then he calmly turned and said: "I'm sorry, I think I've broken my finger", before walking off-stage and being taken to hospital — where he was diagnosed with a dislocated digit.

Beale's understudy, Paul Dodds, who was about to go on in a minor role as a thief, was then hurriedly rushed to change costume to step into his shoes. He took to the stage as Timon to loud applause and gave a performance described as "cracking", "fantastic" and "wonderful", according to audience members on Twitter who sang the praises of Beale and the cast.

Beale yesterday said he was "amazed" at Dodds's ability and that he deserved "huge credit". A show insider said that despite the pain, Beale insisted on showering and changing before heading to St Thomas' Hospital, as the fall happened when Timon is homeless and dressed in dirty, ragged clothes.

Dodds said taking over from Beale was the most "nerve-racking" yet "exhilarating" experience of his career: "The audience and the actors were fantastic. I got a loud round of applause when I went on and the emotional intensity just carried me through."

Beale was due to return to his role last night.