Sinner is pumping his legs and trying to find a way to regain control of the rallies and this match.
But each time he tries something, it seems Medvedev has an answer and that answer is usually to bust his backside, get to the ball and hit a tricky return.
You can see it wearing on Sinner but he is still probing and asking the right questions.
He also has to find some way to attack Medvedev’s serve which continues to hit its marks.
The crowd is trying to lift Sinner - “let’s go Sinner, let’s go” chanted fans during his last service game.
They don’t want this to end, they want a Sinner comeback.