Roger Federer kept waving in apology, twice after he dribbled winners off the net cord and once when he slammed a volley that nearly knocked his opponent down.
Afterward Federer praised 19-year-old American qualifier Frances Tiafoe, a Riverdale resident who acquitted himself well before a near-capacity stadium crowd at the Miami Open. But there are limits to Federer's politeness, and he beat Tiafoe, 7-6 (2), 6-3, on Saturday.
Returning to the tournament after a two-year absence, Federer took the lead with a flawless tiebreaker and gradually pulled away from Tiafoe.
"I think he's going to be really good," Federer said. "He's...