Broadway show Therese Raquin has had a second act of bad luck - an injured Keira Knightley bowed out of a performance, forcing the evening show to be cancelled.

Roundabout Theatre Company said its star suffered "a minor injury" and it expected her to be ready for Thursday night's show.

Knightley, who plays the title character in the play, was on stage on October 1 with Gabriel Ebert when a young man in the mezzanine got up, went to the railing and shouted.

Knightly did not break character, and the man was heard to say: "Five seconds is too long to wait for a response!" An usher escorted the man back to his seat and when security arrived, the man threw the flowers on his way out.

The disturbance took place at the Studio 54 Theatre, the same location where last year actor Shia LaBeouf was handcuffed during a performance of Cabaret for yelling obscenities.

Knightley made her West End debut in 2009 in the comedy The Misanthrope and two years later starred in Lillian Hellman's The Children's Hour.

Last year she revealed that she tore a muscle running through a door while filming The Imitation Game.