STUTTGART, Germany -- Milos Raonic hit 31 aces to beat Australian qualifier Alexei Popyrin 6-7 (6), 6-4, 7-6 (4) in the first round of the Stuttgart Open on Tuesday.
The sixth-seeded Raonic, who lost last year's final to Roger Federer, next faces Jo-Wilfried Tsonga at the grass-court tournament.
Fellow Canadian Felix Auger-Aliassime also won, beating Ernests Gulbis 7-5, 6-3, but Germany's Jan-Lennard Struff defeated Denis Shapovalov 7-5, 6-4. Struff also beat the 20-year-old Canadian in the first round of the French Open.
Fifth-seeded Gael Monfils defeated American Steve Johnson 7-5, 5-7, 7-6 (6).
Denis Kudla had no difficulties against Croatian qualifier Viktor Galovic, winning 6-3, 6-2.
Also, Dustin Brown set up an all-German meeting with top-seeded Alexander Zverev after beating John Millman 6-4, 7-6 (3).
Matteo Berrettini, Lucas Pouille, Marton Fucsovics and Gilles Simon also advanced.
The Stuttgart Open made the switch from clay to grass in 2015.
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