It became an initial 68-round for two strokes under par during the first day of the competition outside Toronto.
Åberg, who started on hole 10, was on par with two holes left to play. Then the 25-year-old answered for two fine approaches and could finish with two straight birdies.
Alex Norén was after the first nine holes one stroke over par, but on the second half it loosened up properly for the 42-year-old. Via four birdies and five pars, Norén came in on 67 strokes for -3.
Jesper Svensson went the first round on -1, Henrik Norlander on par and Tim Widing on +1.
Dane Thorbjørn Olesen played dazzling golf during the opening round. On his last 13 holes, he went nine strokes under par for 61 strokes in total. He now shares the lead with the Chilean Cristobal Del Solar on -9.
Two years ago, Ludvig Åberg made his debut as a golf pro in the Canadian Open. Since then, the Eslöv resident has won two tournaments on the PGA tour, taken a victory on the European tour, played the classic team competition Ryder Cup and finished second in the major tournament US Masters (2024).
Even though Åberg sprinted to a shared 16th place in a major tournament last weekend, the Swedish world eighth had previously missed the qualifying limit in the major tournament PGA Championship and modest placements (54–60) in the two previous tournaments.