Novak Djokovic was full of praise for the "amazing" Denis Istomin after the Uzbek outsider pulled off an incredible upset by beating the defending champion in the second round of the Australian Open.
The 30-year-old wildcard produced the performance of his career at Rod Laver Arena on Thursday, winning a marathon five-set contest 7-6 (10-8) 5-7 2-6 7-6 (7-5) 6-4.
The loss marked Djokovic's earliest grand slam exit since Wimbledon 2008 as he was outdone by a red-hot Istomin in four hours, 48 minutes. The 12-time grand slam champion was below his best against Istomin, a player he had beaten relatively comfortably in their previous five meetings.
Istomin, the world number 117 who won the Asia-Pacific wildcard play-off to earn a place in Melbourne, defied his ranking with a display of incredible shot-making. The opening game took 16 minutes in a sign of things to come, but Djokovic had to come from a break down to force a tie-break in the first set. Djokovic took a 4-1 lead before giving up his advantage, Istomin converting his second set point as he forced his illustrious opponent into an error. Istomin crushed 27 winners in the first set and a drop in level was expected - and came, albeit minor.
Istomin broke for a 3-2 lead in the fifth with yet another screaming winner, a backhand down the line giving him the advantage. The extraordinary win, which set up a clash against Spaniard Pablo Carreno Busta in the third round, was completed with few nerves, Istomin serving out the match to 15.
Djokovic was magnanimous in defeat following an early exit which put paid to his bid to become the first man to win seven Australian Open singles titles.
The world number two said: "All the credit to Denis for playing amazing. He deserved to win. No doubt, he was a better player in the clutch moments.
"He stepped it up, played aggressive. Served very well, very precise. There's not much I could do.
"Of course, I was not pleased with my performance overall. But I have to congratulate my opponent."
Djokovic insisted he was not guilty of taking Istomin lightly.
He added: "There was intensity, of course. We played four and a half hours.
"It's one of these days when you don't feel that great on the court, don't have much rhythm, and the player you're playing against is feeling the ball very well. So that's sport.
"I never underestimate any opponent. Doesn't matter which tournament I play on or which round. I try to give the best that I can. I have respect for everybody.
"Him playing this well, it's amazing. He played obviously above his level. You got to give him credit for that. Many things came together for him. He's a well-deserved winner."