Kei Nishikori of Japan returns a shot against Fernando Verdasco of Spain on Mar 26, 2017. (Photo: AFP/Al Bello) |
Last year's beaten finalist, Nishikori will face Argentine Federico Delbonis who beat Germany's Jan-Lennard Struff.
Verdasco has yet to post a win against a top ten opponent this year but showed plenty of spirit in a two hours 44 minute contest on centre court at Crandon Park fighting back to win a second set tie-break.
But Nishikori stepped up in the third, running away with the set to ensure his progress.
France's Nicolas Mahut beat Argentine Guido Pella 6-4 6-3 and will face the winner of Sunday's clash between Rafa Nadal and Germany's Philipp Kohlschreiber in the last 16.
Injury-plagued world number five Milos Raonic pulled out of the tournament shortly before his match against American Jared Donaldson, citing a recurrence of a hamstring injury.
Raonic originally suffered the injury in the semi-final at Delray Beach and was forced to forfeit the final against American Jack Sock. He then missed this month's Masters event at Indian Wells.
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