Roger Federer has pulled out of his comeback match against Juan Martin Del Potro at the Miami Open with a stomach bug.
The 34-year-old was due to make his return on Friday after suffering a knee injury in January while running a bath for his twin daughters.
The 17-time Grand Slam champion from Switzerland needed arthroscopic surgery to repair a torn meniscus.
His place in the draw is taken by lucky loser Horacio Zeballos of Argentina.
Federer's last match was his Australian Open semi-final defeat to world number one Novak Djokovic.