Milos Raonic should have been the top seed. Still, he had to withdraw, together with Kei Nishikori, Vasek Pospisil, Andy Murray and the reigning champion Reilly Opelka, who didn't want to risk anything ahead of the Australian Open quarantine.
Thus, the Chilean Cristian Garin leads the field, facing Ryan Harrison, Sam Querrey, Mackenzie McDonald en route to the semis. In the second quarter, Hubert Hurkacz and Pablo Andujar are the players to beat, together with the veteran Ivo Karlovic.
The former champion Frances Tiafoe and Adrian Mannarino lead the third quarter. At the same time, John Isner, Tommy Paul and Sebastian Korda seek the semi-final spot from the bottom quarter, carried by the partisan crowd.
In the last year's final, Reilly Opelka prevailed over Yoshihito Nishioka to keep the title at home.