World number one Novak Djokovic came from a set down to beat Greece's Stefanos Tsitsipas in their rain-affected Italian Open quarter-final.
The Serb trailed 6-4 2-1 when the match was suspended because of rain on Friday, but broke serve twice when it resumed on Saturday to force a decider.
He then twice recovered from a break down in a see-saw final set to win 4-6 7-5 7-5 and reach the last four.
Djokovic faces Italian Lorenzo Sonego in the semi-final later on Saturday.
Second seed Rafael Nadal is also in semi-final action against American Reilly Opelka.