Defending champions Team World will carry a 10-2 lead over Team Europe into the third and final day of this year's Laver Cup in Vancouver.
Felix Auger-Aliassime and Ben Shelton added a doubles win for Team World.
"Felix said the job's not done - but we're pretty close," said their captain John McEnroe.
Matches on day three are worth three points so Team World need just one win from Sunday's four contests to win the event for a second time.
Norway's Casper Ruud beat Tommy Paul on Saturday to claim the only points so far for Europe, who won the first four editions of the tournament, which began in 2017.