Novak Djokovic downs Delbonis, Halep battles into Rd 4

Serbia's Novak Djokovic after beating Federico Delbonis. (Right) Halep celebrates a point v Polona Hercog. Pic/AFP

Novak Djokovic remains on course for a record seventh Miami Open title, but the World No. 1 admitted to a loss of focus in a 7-5, 4-6, 6-1 victory over spirited Federico Delbonis which booked his place in the last 16.

Djokovic is hoping to eclipse Andre Agassi's six ATP crowns in South Florida over the next week and although he endured some shaky moments at Hard Rock Stadium, he still possessed enough quality during the key moments to see off the battling Delbonis.

The Serbian will need to tighten up his game if he is to reach next Sunday's final with Roberto Bautista Agut waiting in the fourth round after the Spaniard defeated Italian Fabio Fognini 6-4, 6-4.

In the women's draw, Simona Halep kept alive hopes of regaining the World No. 1 ranking on Sunday, beating Polona Hercog 5-7, 7-6 (7/1), 6-2 to reach the last 16 where she will play Venus Williams. Halep, 27, lost her place at the top of the rankings following Naomi Osaka's triumph at the Australian Open this year.

Catch up on all the latest sports news and updates here. Also download the new mid-day Android and iOS apps to get latest updates