Jasmine Paolini's defense of her Italian Open title came to an early end on Saturday after the home favorite was knocked out in the third round by Elise Mertens, as Jannik Sinner bids to continue his record-breaking Masters 1000 winning streak.
Local favorite Paolini was beaten 4-6, 7-6 (7/5), 6-3 by Mertens following an error-strewn performance in front of disappointed fans on center court.
The 30-year-old is set to drop out of the top 10 of the women's world rankings after failing to reach the fourth round of a fourth consecutive tournament.
Paolini won both the women's singles and doubles tournaments in Rome last year but she has looked a shadow of that player this season with a string of early exits.
Her fate turned on her failure to capitalize on three match points against the serve at 6-5 in the second set, after which she lost the first two points of the tie-break and never recovered from there.
"I didn't make the most of my chances, I needed to keep a clearer head, keep my cool better in those moments," Paolini told reporters, according to AFP.
"I'm very disappointed to lose but there were moments in which I felt good on the court and I was competitive and positive."
Mertens, who lost last year's women's doubles final to Paolini and Sara Errani, could face eighth seed Mirra Andreeva in the next round.
Coco Gauff, beaten by Paolini in last year's singles final, took over two hours to beat Argentina's Solana Sierra 5-7, 6-0, 6-4.
The world number four and reigning French Open champion will face either her fellow American Taylor Townsend, a qualifier, or Iva Jovic in the next round.
Gauff has struggled on clay this season, with a last-16 exit in the Madrid Open coming after a disappointing run to the quarter-finals in Stuttgart.
The 22-year-old is on the same side of the draw as world number one Aryna Sabalenka, who faces Romania's Sorana Cirstea.
Sinner will take to an expectant center court later on Saturday as a hot favorite to extend his run of five consecutive Masters 1000 tournament victories.
Austria's Sebastian Ofner stands in the way of Sinner winning a 24th straight match, with few expecting anything more than a rapid victory in straight sets.
No Italian man has won at the Foro Italico since Adriano Panatta 50 years ago, and with Carlos Alcaraz out of action Sinner is expected to go one better than last year when he lost the final to his great rival.
Former winner Daniil Medvedev will begin his campaign in the third round after his match, which was scheduled to be the first on center court, was shelved after his opponent Tomas Machac pulled out of the tournament with an unspecified illness.
Fourth seed Felix Auger-Aliassime suffered a shock second-round defeat at the hands of Argentina's Mariano Navone, the Canadian losing to his 44th-ranked opponent in straight sets 7-6 (7/4), 7-6 (7/5).
