Alexander Bublik sank to a straight sets defeat to Jannik Sinner in the Miami Masters quarter-final before saying the Italian was so good he doesn't even seem human.
The Kazakhstani put in an enviable performance himself, and threw everything including underarm serves at 19-year-old Sinner to try to overcome him.
Sinner, though, refused to buckle, leading to Bublik saying to him on court following match point: “You are not a human, man. You are 15-years-old [sic] and you play like this. Good job.”
That praise continued after the match too, with Bublik continuing to be awe-struck with what he had witnessed.
“He's not [human]," he said of Sinner. "That's a fact.
“I asked him if he's a human or not, because for me, it's very surprising that the guy at his age has this mental toughness that many, many other players don't have.
"I called him a robot a couple of times during the match, but I do it in a very sincere way because he's a really, really a great player.
“I played him in a very crucial moment in the tie-break, and [he] pulled off [two] incredible shots when it was 5/4.
“Every time when I had a big point, either I needed to go super crazy like I was doing with the forehand and just [go for a] shot that goes in with a five per cent chance, or he's playing really unbelievable.
Jannik Sinner is the eighth teenager to reach the Miami semi-finals, with five of the other seven going on to become world number one.
He will now face Roberto Bautista Agut in the semi-finals, with him guaranteed a new-career high ranking of at least number 24 in the world next week.
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