MIAMI (AFP) - Japan's Kei Nishikori came through a tough test against Spaniard Fernando Verdasco, 7-6 (7/2), 6-7 (5/7) 6-1 at the Miami Open on Sunday (March 26), his three sets win taking him into the last 16.

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.