Rome: World number three Roger Federer pulled out of the Italian Open before his quarter-final match on Thursday with a right leg injury.
Federer, a four-time Rome finalist, had been due to meet Greek eighth seed Stefanos Tsitsipas for a place in the semi-finals.
The Swiss 20-time Grand Slam winner was playing in Rome to prepare for his return to the French Open for the first time since 2015.