According to Variety, Schiff's understudy, Adam Morris, was called to step in without a single rehearsal.
Representatives for the production, which began Sept. 24, confirmed that Schiff resumes performances Sept. 29.
The work will officially open Oct. 2 at the Playhouse Theatre for a limited run through Nov. 29. It also features established screen and stage actor Nigel Lindsay.
The play revolves around a pair of film producers Bobby Gould (Schiff) and Charlie Fox (Lindsay). When a hugely bankable star agrees to appear in a sure-fire commercial hit, they are convinced this is the break of a lifetime. That is until temporary secretary Karen (Lohan) derails the dream. When she persuades Bobby to dump the blockbuster in favour of a story which can only be described as box-office poison, Charlie is forced to resort to desperate measures.
The production is directed by Lindsay Posner, who has directed more Mamet plays in the West End than any other director, including A Life in the Theatre, Sexual Perversity in Chicago and Oleanna.
It is produced by Danny Moar and Simon Friend for Theatre Royal Bath Productions.
To book tickets, contact the box office on 0844 871 7631 or visit www.atgtickets.com/speed-the-plow.