He's torn his abdomen, meaning he can't play today's semi-final with Nick Kyrgios.
Britain's Cam Norrie takes on defending champion Novak Djokovic - who's chasing a seventh title - to see who will join him in the showpiece.
Yesterday, number three seed Ons Jabeur won through to face Kazakhstan's Elena Rybakina in the final of the women's singles.
Both players are into the final of a major tennis tournament for the first time in their careers.