Gael Monfils upset Marin Cilic 6-3, 7-6 to advance to the quarterfinals of the Rio Open.
Monfils finished Cilic off in 5 minutes after their match was interrupted by heavy rain on Wednesday night.
Next up for Monfils is No. 6 seed Daniel Schwartzman.
The Frenchman said waiting to play the decisive points against Cilic was very hard.
"We only played four points, but I had to keep my concentration all day long. I am so glad I could do that," Monfils said.
Dominic Thiem moved on to the next round when Pablo Andujar retired due to injury in the seventh game of their match.
Thiem, who won the Rio Open last year, will face Fernando Verdasco in the quarters. Verdasco beat Nicolas Kicker 6-7, 6-2, 6-0.
Fabio Fognini also advanced with a 4-6, 6-4, 7-6 victory against Tennys Sandgren.
The Italian will face Alijaz Bedene, who eliminated No. 3 seed Pablo Carreno Busta with a 6-2, 5-7, 6-2 win.
