Thanasi Kokkinakis has recorded the biggest win of his career with a three-set victory over world No.1 Roger Federer at the Miami Open.

The 21-year-old Australian dropped the first set before he improved his game to stun the defending champion 3-6 6-3 7-6 (7-4) in their second-round match.

Kokkinakis, the world No.175, needed two hours and 21 minutes to hand Federer just his second loss in 2018 and leave a near-capacity crowd stunned.

He will face veteran Fernando Verdasco in the next round after the 31st-seeded Spaniard defeated countryman Guillermo Garcia-Lopez 6-4 0-6 6-2.

In addition to qualifier Kokkinakis, it was a good day for a number of other young guns.

German fourth seed Alexander Zverev mounted a fightback in his opener after a bye, overcoming Russian Daniil Medvedev 6-4 1-6 7-6 (7-5).

Canadian teenager Denis Shapovalov swept the first set in 23 minutes as he crushed Damir Dzumhur 6-1 7-5.

Croatian Borna Coric came from a set down to oust Argentinian Leo Mayer 6-7 (5-7) 6-3 6-4.

American Frances Tiafoe was two points from defeat but battled to to rally past British seed Kyle Edmund 7-6 (7-4) 4-6 7-6 (7-5).

Czech 10th seed Tomas Berdych eased past Yoshihito Nishioka 6-1 6-4 while 35-year-old Spaniard David Ferrer beat young Russian Evgeny Donskoy 6-2 6-2.

Others to progress to the round of 32 were 11th-seeded American Sam Querrey, Italian 15th seed Fabio Fognini and Karen Khachanov.