Roger Federer’s winning run continued as he disposed of Juan Martin Del Potro in straight sets at the Miami Open on Monday.
Federer won 6-3 6-4 in the third round having last week captured the title at Indian Wells, after beginning 2017 with the Australian Open title.
The Swiss veteran's brilliant start to the year, after an injury-disrupted 2016, has seen his world ranking improve to sixth and outclassing Del Potro is a further step in the right direction considering the world's top two players, Andy Murray and Novak Djokovic, withdrew from Miami.
Fourth seed Federer's two titles in Miami came back-to-back in 2005 and 2006 but he easily outclassed Del Potro, whose form since recuperating from his own injury woes has been far shakier than his more illustrious opponent's.
Next up for Federer will be Roberto Bautista Agut, who came from behind to see off Sam Querrey 2-6 6-2 6-3.
Federer is joined in the fourth round by his compatriot Stan Wawrinka after an easy outing for the top seed.
Wawrinka beat Tunisian Malek Jaziri 6-3 6-4 and will meet rising star Alexander Zverev, who won an epic encounter against John Isner.
The German triumphed 6-7 (7/5) 7-6 (9/7) 7-6 (7/5), saving three match points, in a match that went on for two hours and 40 minutes.
Nick Kyrgios also prevailed in a titanic battle with big-serving Ivo Karlovic, winning 6-4 6-7 (7/4) 7-6 (7/2).
The young Australian's next opponent will be David Goffin, who also fought back from a set down to beat Diego Schwartzman 3-6 6-3 7-5.
Meanwhile, Tomas Berdych beat Gilles Muller 6-3 6-4 and will now face Frenchman Adrian Mannarino, a 6-4 2-6 7-6 (7/3) winner over Borna Coric.
