Tiafoe had a really great showing last year in Tokyo, making his way to the final, where Taylor Fritz beat him. He naturally returned this year, hoping to do the same even though his form in recent weeks hasn't been very good.
Well, he didn't play that well today either, losing surprisingly to Aslan Karatsev who is a capable player but very streaky. He's either very good or very bad, and today he was pretty good.
The opening set featured very poor serving from Tiafoe, and on a fast court like the one in Tokyo, that's a problem. It's a big problem because he was dominant behind his first serve but hit it only 40 % of the time and that gave Karatsev chances which he took.
The second set was a bit better for Tiafoe because he served better, but then he also wasted a couple of really solid chances. Even in the first set, Tiafoe had break points but struggled to convert them, which was a theme for him in the match.
The second set saw Tiafoe jump out to a 4-1 lead, but he gave it back, which was a problem as he had to play a tiebreak that can be very volatile in such conditions.
He actually jumped out to a 4-1 lead in the tie-break but then suffered an epic collapse, losing six straight points on a court where a good serve is basically 90 % of the point. That's shocking and shows that he's not having a very good conclusion to the year.
It was evident at the US Open, where he played far worse than last year. It's somewhat surprising after he won two trophies earlier this year.