Four-time champion Novak Djokovic beat Roberto Bautista Agut 6-4, 6-4 Thursday to ease into the quarterfinals of the Italian Open.
Djokovic seemed in full control when he went 3-1 up in the second set but allowed the Spaniard to fight back to 4-4 before going on to seal the match.
Bautista Agut could have gone 5-4 up in the second set after Djokovic appeared to send the ball long but the umpire said it was in. Television replays showed the ball was out.
Instead it was Djokovic who broke to take a 5-4 lead and won the match when he had a forehand ruled in.
Djokovic next faces either Kei Nishikori or Juan Martin Del Potro.
Third-seeded Stan Wawrinka went out of the tournament after losing 7-6 (1), 6-4 to American John Isner, who served up 19 aces in their match.
Isner grabbed the only break of the match at 3-3 in the second set before comfortably serving out the match on his first attempt after Wawrinka had saved two match points on his serve.
Isner next faces another big server in sixth-seeded Marin Cilic, who dismissed ninth-seeded David Goffin 6-3, 6-4.
Jack Sock will be hoping to pull off an even bigger shock than fellow American Isner when he takes on Rafael Nadal later.
Home favorite Fabio Fognini, who saw off Andy Murray on Tuesday, lost 6-3, 6-3 to Alexander Zverev, who will play fifth-seeded Milos Raonic in the quarterfinals after the Canadian beat Tomas Berdych 6-3, 6-2.
In the women's draw, Venus Williams defeated Johanna Konta 6-1, 3-6, 6-1.
Konta had won her previous three meetings against Williams but the American dominated the first set. Although Konta rallied in the second, another double break in the third handed Williams victory.
Williams will take on Garbine Muguruza after the 2016 French Open champion beat Julia Gorges 7-5, 6-4.
Estonian qualifier Anett Kontaveit, who beat top-ranked Angelique Kerber in the second round, continued her dream debut. Kontaveit beat 16th-seeded Mirjana Lucic-Baroni 6-1, 6-1 to set up a quarterfinal against Madrid Open champion Simona Halep.
The sixth-seeded Halep beat Anastasia Pavlyuchenkova 6-1, 4-6, 6-0.
Qualifier Daria Gavrilova beat seventh-seeded Svetlana Kuznetsova 2-6, 7-5, 6-4 and Kiki Bertens won 7-6 (3), 6-1 over Russia's Ekaterina Makarova.