Alexander Zverev continued to limber up for a potential US Open title challenge with a four-set win over American Brandon Nakashima.
The fifth seed may have been some levels below his best but he got the job done to advance to round three in a tournament lacking perennial contenders Roger Federer and Rafael Nadal.
The 23-year-old came through 7-5 6-7 (8) 6-3 6-1 in two hours and 55 minutes despite a second set scare when he struggled to maintain momentum on his serve.
Zverev, who will next face 32nd seed Adrian Mannarino, shrugged off the impact of the absence of those major names on his bid to break his grand slam final duck.
"They're two players who are not here and they're two of the greatest, so obviously it will have a little bit of an effect," said Zverev.
"But this year's US Open is different in many ways - we don't have spectators, the crowd is gone, and stuff like that.
"Obviously it's not the same, but at some point those two will retire as well. And we will play every tournament without them."
Belgian seventh seed David Goffin also advanced to the third round with a four-set win over South Africa's Lloyd Harris in a match lasting just under three hours.