Top seed Kei Nishikori has overcome a scare to progress to the last eight of the Argentina Open.
The world No.5 five dropped the first set to home hope Diego Schwartzman in Buenos Aires but recovered to record a 5-7 6-2 6-2 victory.
Nishikori will face Joao Sousa in the last eight after the sixth seed overcame Federico Delbonis 7-5 6-3.
Fourth seed Pablo Carreno Busta beat qualifier Alessandro Giannessi to set up a quarter-final meeting with fellow Spaniard Albert Ramos-Vinolas, who prevailed after Leonardo Mayer had to retire in the deciding set.
Eighth seed Paolo Lorenzi suffered a first-round exit, with the Italian losing 6-3 6-3 to Gerald Melzer.