Madrid Masters: Inconsistent Novak Djokovic makes shocking admission after latest early exit

Arnaldi, who collected his second victory over a top-five player, served out the match with ease for a 6-3, 6-4 win to move into the third round of the ATP Masters 1000 event.

The last time that the former world No. 1 left Madrid without a victory was back in 2013, when he lost to Grigor Dimitrov in the round of 32 in a three-set tussle.

This encounter, however, cannot be described as such, with Djokovic several levels below his Madrid best.

"It could be [my last match in Madrid]," admitted a dejected Djokovic.

"I'm not sure if I will come back. So, I don't know, I don't know what to say. I mean, I'll come back, maybe not as a player, of course. I hope it's not, but it could be.

Meanwhile, Arnaldi was over the moon.

"Yeah, pretty much [it feels like a dream] without any doubt," remarked the Italian.

"He's my idol, he has always been, so I was just glad that I could play him [Djokovic] because I had never played him - just practised once.

"So, to play him on a stage like this was already a victory for me, but, he's not at his best right now, so I came on the court to try to play my best tennis and win, and it happened.

"Right now, I don't even know what to say."

The Italian had battled through a tough three-set match in the first round against Born Coric, but looked far more comfortable in the Manolo Santana stadium, with a crucial hold at 4-3 in the second after facing three break points proving critical.

In the end, Arnaldi utilised his second match point to claim the biggest win of his career.

"At the start, I just tried to not s*** in my pants to be honest," said the world No. 44, who will next face Damir Dzumhur.

"That was the main thing because, when I got on this court - I had never even practised on this court - so you don't know anything, you don't know the points of the court.

"Playing him, I just tried to rally a bit at the start, try to make him make mistakes. Then, the tension started to go away, and he gave me a little bit in a few games.

"For sure, when I broke him, I knew that I was going to be broken back straight after, then I was like 'ok, that's a good start.' After that, it was an escalation and it became quite a good match.

"I have to watch the match again. Like I said, I have been watching him play since I was a kid, nine, ten, I always tried to play like him, so, at that point [in the 4-3 game in the second set], we were pretty similar and I won that point."

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