World No.4 Dominic Thiem found himself at the centre of extraordinary scenes in Rome as he was sensationally knocked out of the Italian Open.
Thiem was ousted from the clay court tournament in a marathon three-set battle against Italy's Lorenzo Sonego, who eventually prevailed 6-4, 6-7 (5/7), 7-6 (7/5).
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Sonego enjoyed the support of home fans but curiously, only for the first two sets.
Supporters returned to the stadium for the first time but because of an enforced Covid-19 curfew, they had to leave by 10pm.
The strange scenes meant the match had to be delayed briefly between the second and third set after Thiem had just taken the absorbing contest into a deciding set.
It brought back memories of Novak Djokovic's win over Taylor Fritz at the Australian Open in February, when fans inside Rod Laver Arena were forced to leave at midnight to comply with a Victorian Covid-19 lockdown.
In Rome, fourth seed Thiem had just claimed the second set in a thrilling tiebreaker but any momentum he may have taken into the decider was effectively snatched away in scenes that left viewers confused and a little frustrated.
The break in play allowed Sonego to regroup for the third set, where he was forced to come back from a match point down to force a tiebreak.
Despite missing the support from home fans, the World No.33 came up clutch at the death to send Thiem packing in a stunning upset.
"It's amazing, unbelievable, an emotional moment for me," said Sonego who upset world number one Novak Djokovic last year in the quarter-finals in Vienna.
"I'm at home, in front of the fans. I'm so happy for this victory, because along with (Rafael) Nadal he's the best player on clay."
Big guns roll on in Rome
Sonego next meets Russian Andrey Rublev for a place in his first Masters semi-final having reached the last eight in Monte Carlo two years ago.
Elsewhere, top seeds Novak Djokovic and Rafael Nadal reached the quarter-finals alongside fellow former winner, Alexander Zverev, who maintained his impressive recent form.
Nine-time champion Nadal had to save two match points against Canada's Denis Shapovalov in a 3-6, 6-4, 7-6 (7/3) battle over nearly 3hr 30min.
Nadal will next play last week's Madrid Masters winner Zverev, the sixth seed, who needed nearly three hours to see off Japan's Kei Nishikori 4-6, 6-3, 6-4.
Nadal lost to Zverev, 24, in the Madrid quarter-finals last week with the German, also a former Italian Open winner, having beaten Djokovic in the 2017 final.
Djokovic and Nadal have won 14 of the last 16 Rome titles between them, playing each other in the final five times.
Djokovic, a five-time Rome winner, next plays Monte Carlo champion Stefano Tsitsipas who ended the run of home hope Matteo Berrettini 7-6 (7/3), 6-2 in one hour and 36 minutes.
It will be a rematch of last year's French Open semi-final which the Serbian won.
"It always feels like home coming back to Rome," said Djokovic, who has never failed to reach the quarter-finals in his 15 appearances in the clay-court event.
In the women's, World No.1 Ash Barty set up a clash with "extremely dangerous" US teenager Coco Gauff for a place in the semi-final.
The top-seeded Aussie won 6-3, 6-3 against Russian Veronika Kudermetova after 17-year-old Gauff earlier ousted Madrid Open winner Aryna Sabalenka.
Sabalenka shocked Barty, 25, in last weekend's Madrid final and the 2019 Roland Garros winner conceded she was wary of her first meeting with Gauff.
"Coco has shown that she loves to bring her best tennis against the players that challenge her the most," said Barty.
"She's extremely dangerous."
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