Rome - Rain-interrupted play at the Rome Masters was set to resume on Saturday after heavy downpours and storms in the Italian capital.
Organisers called a halt to proceedings late on Friday as Serbian second seed Novak Djokovic, a four-time champion, took a one-set lead over quarter-final opponent Juan del Potro of Argentina.
Their match was stopped after Del Potro took a 2-1 lead in the second set.
Despite thunderstorms and heavy rain throughout the night the bad weather finally abated at midday, prompting organisers to announce: "We're working hard to start as soon as possible."
First up is a women's semi-final between Romanian sixth seed Simona Halep and Dutchwoman Kiki Bertens, seeded 15th.
The second women's semi-final will see Spain's number three seed and reigning French Open champion Garbine Muguruza face Ukrainian eighth seed Elina Svitolina.
The first men's semi-final is between 20-year-old German starlet Alexander Zverev and big-serving American John Isner.
Austria's Dominic Thiem, who sent seven-time champion Rafael Nadal crashing out in their quarter-final, is set to face the winner of the Djokovic-Del Potro quarter-final later in the day.