Top-seed Matteo Berrettini has overcome rain delays and a tough home country opponent to advance to the quarter-finals of the rain-plagued Rio Open clay-court tournament.

The Italian world No.6 beat Thiago Monteiro 6-4 6-7 (8-6) 6-3 in a match that was initially scheduled for Thursday evening, but ended only minutes before Saturday began in Rio de Janeiro.

“I had two match points in the second set, but Thiago was strong,” said Berrettini, recalling moments of the match that took place seven hours before he could play the last points.

“Here I am near midnight, playing. You have to be strong mentally.”

Berrettini’s adversary will be Spain’s Carlos Alcaraz, who beat Argenina’s Federico Delbonis 6-4, 7-6 (7-1) after several interruptions due to rain.

Rain forced organisers to postpone all quarter-final clashes until Saturday.

Besides the Berrettini-Alcaraz clash, Argentina’s Diego Schwartzman will face Spain’s Pablo Andujar, Serbia’s Miomir Kecmanovic will play Argentina’s Francisco Cerundolo, and Italy’s Fabio Fognini will take on Argentina’s Federico Coria.