BUENOS AIRES, Argentina — Top-seeded Kei Nishikori is finding his footing on clay.

After struggling in his first match in the Argentina Open, the Japanese player beat No. 6 Joao Sousa of Portugal 6-1, 6-4 on Friday to reach the semifinals in the outdoor clay-court event.

Nishikori will face Carlos Berlocq of Argentina, a 3-6, 6-2, 6-3 winner over Thiago Monteiro of Brazil.

Spain's Pablo Carreno Busta will play the Ukraine's Alexandr Dolgopolov in the other semifinal. Carreno Busta beat fellow Spaniard Albert Ramos-Vinolas 6-3, 4-6, 6-4, and Dolgopolov topped Austria's Gerald Melzer 7-5, 6-4.