MIAMI • World No. 1 Novak Djokovic made a strong start on Friday in his quest for a third consecutive Miami Open title while Roger Federer's expected return from a two-month lay-off was over before it started.
Djokovic, seeking his sixth Miami crown overall and the first hat-trick of titles since Andre Agassi from 2001-2003, opened by defeating Britain's 87th-ranked Kyle Edmund 6-3, 6-3 in the ATP and WTA hardcourt event.
"I had a solid performance," Djokovic said. "I started with the right intensity and good focus. I had slight ups and downs. I'm pleased. I'm looking forward to the next one."
Djokovic, who captured his 11th Grand Slam singles crown at the Australian Open two months ago, will face Portugal's Joao Sousa in the third round today as he tries to add to a 2016 trophy haul that also includes titles in Doha and Indian Wells.
The 28-year-old Serb is 23-1 this year and has won 25 of his past 26 Miami matches, including 11 in a row.
But third-ranked Federer, the 17-time Grand Slam singles champion who underwent left knee surgery last month, withdrew from the tournament just hours before his match, citing a stomach virus.
"I have not felt great for a few days and unfortunately it got worse in the last 24 hours," he said.
"I was really excited to have my comeback in Miami but I am in no condition to play. I tried to warm up this morning but it was clear that I could not compete."
The Swiss has not played since losing to Djokovic in the Australian Open semi-finals two months ago, and initially had not expected to be ready from his injury in time to play at Miami, but he recovered well from the operation.
Meanwhile, reigning Australian Open champion Angelique Kerber and Spanish fourth seed Garbine Muguruza, last year's Wimbledon runner-up, reached the third round.
German second seed Kerber cruised past Czech Barbora Strycova 6-1, 6-1 while Muguruza battled for 2hr 45min before subduing Slovakia's 54th- ranked Dominika Cibulkova 6-7 (3-7), 6-3, 7-5.
Next up for Kerber, whose best Miami showing was a 2014 quarter-final run, is 108th-ranked Dutch qualifier Kiki Bertens. Muguruza will meet American wild card Nicole Gibbs.
"It's time to get on court and work hard again and do the same things that made me strong before Australia, getting ready for my next matches and tournaments," said Kerber.
Tenth seed Venus Williams, a seven-time Grand Slam singles champion and three-time Miami champion, was eliminated by Russian qualifier Elena Vesnina 6-0, 6-7 (5-7), 6-2.
AGENCE FRANCE-PRESSE, REUTERS
ATP MIAMI OPEN
Day 5, Session 1: StarHub Ch201, 11pm