Zverev was serving well when he has already collapsed physically. Before that could have won the third set easliy if he had the good service at this time.
His service will be a big weapon in the future. His backhand was great until the last. His forehand wasn't reliable it was even awful.
And in the end we have to say he had to pay the bill for the mondaygame. I'm happy with his first grass court season.