Japanese top seed Kei Nishikori lost a sixth successive final on Sunday when he was defeated by Ukraine's Alexandr Dolgopolov 7-6 (7/4), 6-4 in the Buenos Aires clay-court title match. The world number five had already lost in the Brisbane final in January to Grigor Dimitrov which followed 2016 defeats in tournament deciders in Basel (against Marin Cilic), Toronto (Novak Djokovic), Barcelona (Rafael Nadal) and Miami (Djokovic).
"I'm happy to be in the final. Unfortunately I lost today, but Alex played better than me. I didn't play badly, so hopefully I can keep this level going," said Nishikori.