Alexander Zverev said that Jannik Sinner is as good as Novak Djokovic at his peak and on "a different universe" after the German was well beaten in Sunday's Australian Open final.
Top-ranked Italian Sinner retained his Melbourne crown with a ruthless 6-3, 7-6 (7/4), 6-3 victory over the second-seeded Zverev.
It was 23-year-old Sinner's third Grand Slam title, having also won the US Open.
Zverev said he felt almost powerless against an opponent he admitted was better in almost every facet of the sport.
"He's very, very similar to Novak when he was at his best," Zverev said, drawing favourable comparisons between Sinner and 24-time major champion Djokovic.
"They barely miss, they make you think like you have to overhit all the time to have a chance in a rally against them.
"It's very, very difficult to win a point from the back of the court against them, against Novak and him.
"They're constantly on the baseline. They don't give you any space. They don't give you any time.
"I mean, just right now too good for me."
Sinner is especially formidable on hard courts.
"He's in a different universe right now to anyone else," said Zverev, adding that "now it's like he's prime Novak".
The 27-year-old Zverev has still never won a Grand Slam title despite having been in three major finals.
"I don't want to end my career as the best player of all time to never win a Grand Slam, that's for sure," said the world No 2.
"I'll keep doing everything I can to lift one of those trophies."