Djokovic on course for seventh Miami Open title

The former world No.1 will now face Bulgaria's Grigor Dimitrov in Friday's semi-finals. Djokovic is 12-1 against the 33-year-old Dimitrov, who reached the tournament finals last year.

Djokovic, who won all his of his titles at the tournament's previous venue at Key Biscayne, is hunting his 100th professional title.

"Overall I've been playing very well the entire week,'' Djokovic told Tennis Channel after the match.

With the Hard Rock Stadium fans cheering the 37-year-old and chanting his name despite him facing an American opponent, Djokovic rallied in the second set from 4-1 down to win in a tiebreaker.

He served an ace on match point and finished with an 83 first-service percentage against the 24th-seeded Korda. The 37-year-old Serbian let out a yell after the victory and strummed his racket like a violin.

The men's leader in grand slam titles at 24 has been out of form this year, starting with an injury retirement at the Australian Open in January. Earlier this month, Djokovic lost his first match in the first leg of this "Sunshine Double'' at Indiana Wells to Botic van de Zandschulp.

Korda, son of grand slam champion Petr Korda who grew up at the Bradenton, Florida, tennis academies, had beaten a top-10 opponent in Stefanos Tsitsipas earlier in the tournament and played at a flawless level to build a 4-1 second-set lead before Djokovic found his phenomenal game.

In the day's first men's quarter-final, unseeded teenager Jakub Mensik beat 17th-seeded Arthur Fils 7-6 (7-5) 6-1.

The 19-year-old Mensik advanced to his first semi-final at an ATP 1000-point level event.

Mensik, of the Czech Republic, squeaked out the tiebreaker and then stormed to a 4-0 lead in the second set to knock out the 20-year-old Frenchman.

The 54th-ranked Mensik hit 13 aces and a crosscourt forehand winner that ended the match in 75 minutes.

Mensik will face the winner of Thursday night's Taylor Fritz-Matteo Berrettini quarter-final.