The second seed defeated German Cedrik-Marcel Stebe 7-5 6-3, saving all three break points faced. He hit an impressive 11 aces and looks like the man to beat in Delray Beach.
He next faces unseeded American Steve Johnson, who defeated countryman Jack Sock 6-4 5-7 6-1 in two hours and 5 minutes. After getting his first win in over a year in the previous round, Sock was unable to replicate that performance against Johnson.
American Frances Tiafoe battled past compatriot Tommy Paul 7-5 7-6(4) in an hour and 46 minutes. The 2018 champion saved two break points and fought back from 2-5 down in the second set to advance to the quarterfinals.
Awaiting Tiafoe is sixth-seeded Frenchman Ugo Humbert. The reigning Auckland champion prevailed against Serbian Miomir Kecmanovic 6-4 7-6(4), avenging last week's loss at the New York Open. Tiafoe leads Humbert 1-0 in career meetings, taking their sole encounter at the 2019 Next Gen ATP Finals.
[embed]https://twitter.com/TennisTV/status/1230607233442078721[/embed]