A senior violinist and veteran of the Bolshoi theatre for four decades has died after falling into the orchestra pit.
Viktor Sedov, 65, played in the second violins.
Katerina Novikova, spokeswoman for the Moscow theatre, said the incident happened on Tuesday and Sedov died of his injuries in hospital on Wednesday.
She said he was much loved at the world-renowned venue for his "sense of humour and extraordinary erudition".
The exact circumstances of the incident remain unclear.
Mr Sedov's death comes at a time of high drama for the theatre. Earlier this month the Russian government replaced its head, Anatoly Iksanov, whose reign has been characterised by a series of scandals.
Repeated allegations of huge corruption during the building's renovation in recent years were compounded by the horrific acid attack on Sergei Filin, head of the ballet troupe, in January.
A dancer, Pavel Dmitrichenko, was arrested for ordering the assault and is currently awaiting trial, while Mr Filin is still undergoing treatment in Germany and has lost most of his sight.