Up to 1,000 spectators have been allowed by the Italian government to be present at the final two days of the tournament in Rome.
World number one Novak Djokovic and defending champion Rafael Nadal have welcomed the decision to allow a limited number of fans to watch the Italian Open as the top men's seeds advanced to the quarter-finals on Friday.
Italy's government have said that 1,000 spectators can be present at the Foro Italico from Sunday's semi-finals, with matches so far being played in empty courts.
"If it's safe enough, fantastic," said Nadal after sweeping past Serb Dusan Lajovic 6-1, 6-3 in his third round match.
Djokovic battled past fellow Serb Filip Krajinovic 7-6 (9/7), 6-3, to remain on a collision course for a final showdown with Nadal for a second consecutive year.
'A thousand motivations'
"A thousand people is better than no people, for sure, because we all miss the fans," said Djokovic.
Men's fourth seed Matteo Berrettini, the only Italian remaining in the tournament, regretted he could not benefit from spectators for his quarter-final against Norway's Casper Rudd on Saturday.
"A thousand people isn't insignificant, it's a thousand motivations," said Berrettini.
Nadal proved too strong for 25th-ranked Lajovic, who had valiantly but vainly launched a fightback after trailing 4-0 in the second set to the Spaniard.
But Krajinovic made long-time friend Djokovic work hard to reach the quarter-finals for the 14th time, just one fewer than Nadal.
Djokovic double faulted on the first of his three set points in the first-set tiebreak but a quick break in the second put him through in a tournament he has won four times.
"Never easy, I think, emotionally to play against someone that is one of my best friends for many years," said Djokovic.
The top seed is warming up for the French Open in 10 days time, having made the switch from the American hard court tour where he won the Cincinnati tournament played in Flushing Meadows before the US Open from which he was disqualified.
He next plays German qualifier Dominik Koepfer who ended the run of Italian teenager Lorenzo Musetti 6-4, 6-0.
World number two Nadal takes on Argentine eighth seed Diego Schwartzman, who dropped a set before recovering to see off Poland's Hubert Hurkacz 3-6, 6-2, 6-4.
Nadal, 34, won his first Rome title back in 2005, and is bidding for a third consecutive crown on clay in the Italian capital and 10th in total.
The 12-time French Open champion is returning to competition, having not played since winning in Acapulco in February.
Halep, Pliskova advance
Top women's seed Simona Halep and defending champion Karolina Pliskova also eased into the quarter-finals, along with two-time Rome winner Elina Svitolina.
Halep rallied from 0-3 down in the first set to see off Ukraine's Dayana Yastremska in a 7-5, 6-4 victory in one hour and 28 minutes.
The two-time Rome finalist next meets Yulia Putintseva, who came back from 6-4, 5-2 down to dispatch fellow Kazakh Elena Rybakina, the 10th seed, 4-6, 7-6 (7/3), 6-2.
"I expect a tough battle but I feel fit," said former French Open champion Halep, a runner-up in Rome in 2017 and 2018 to Svitolina, who got past two-time Grand Slam winner Svetlana Kuznetsova 7-6 (8/6), 6-4.
Halep said she was looking forward to the "good energy" generated by the crowd.
"It will interesting and nice to have some people in the stands."
Ninth seed Garbine Muguruza advanced to her sixth quarter-final this year with a straight-sets win over last year's Rome finalist Johanna Konta.
The former French Open winner will next face US Open finalist Victoria Azarenka.