Miami, FL (SportsNetwork.com) - Four-time champion Novak Djokovic beat Steve Darcis 6-0, 7-5 on Monday to reach the fourth round of the Miami Open.

The top-seeded Djokovic fell behind 5-4 in the second set when the qualifier converted his only break-point chance of the match. But Djokovic broke Darcis' serve to level the set and again two games later.

Djokovic, who topped Rafael Nadal in last year's Miami Open final, will next face Alexandr Dolgopolov.

In other action, No. 4 seed Kei Nishikori tallied five service breaks as he rolled past 32nd-seeded Viktor Troicki 6-2, 6-2 in 63 minutes at Crandon Park.

"I was almost perfect on the court this morning," said Nishikori, a semifinalist at this Masters 1000 event last year. "It's really exciting that I'm playing good here. Maybe he was hurting a little bit, but still I was giving him a lot of pressure with my return. He has a great serve. So I think it was a great game today."

Milos Raonic, seeded fifth, swatted 20 aces before sneaking past No. 31 seed Jeremy Chardy 6-1, 5-7, 7-6 (7-3). No. 6 seed David Ferrer also advanced, beating 26th-seeded Lukas Rosol 6-4, 7-5.

Another Day 6 result saw American John Isner post a 7-6 (7-2), 6-2 win over No. 9 seed Grigor Dimitrov.

This weekend's champion will earn $900,400.