Two of three Canadians won first-round matches on Tuesday at the Stuttgart Open in Germany.
Shapovalov lost 7-5, 6-4 to Jan-Lennard Struff in a rematch of a French Open first-round match won by the German in straight sets. Struff, ranked 38th in the world had 14 aces in his latest win over Shapovalov.
Auger-Aliassime, who reached a career-high No. 21 in the world rankings this week, dropped out of the French Open with a left abductor injury after advancing to the final of the Lyon Open the previous week.
Raonic, playing for the first time since suffering a right knee injury in late March, hit 31 aces to edge Australian qualifier Alexei Popyrin 6-7 (6), 6-4, 7-6 (4). The Canadian was dominant with first serve, winning 47 of his 50 points.
Raonic, the runner-up in Stuttgart last year, will face France’s Jo-Wilfried Tsonga in the second round.