#4 Alexander Zverev
Alexander Zverev (GER) lost to Ernests Gulbis (LAT) 6-7(2), 6-4, 7-5, 3-6, 0-6

Alexander Zverev, the world number three, hit a wall physically after a gruelling battle with Ernests Gulbis. The Latvian maverick is also known for his impressive victory over Federer in the 2014 French Open, where he came from 2-1 down to take the match in five sets. It was the first time Gulbis had won three straight matches in a row since 2016 Roland Garros.
Zverev has not lived up to his potential in Grand Slams, which he has been showing at ATP Masters events. He has never gone past a Grand Slam quarter-final, which is a disappointment for a player with high potential.
Tiredness also cost him the match as the best-of-five is always physically demanding, and in the post-match interview, he admitted that he had not eaten for 24 hours due to a stomach bug.