The American star missed the cut at The Open but Johnson has regrouped in Canada, setting the Glen Abbey Golf Course alight with a sizzling penultimate round.
The top-ranked Johnson, who has an endorsement deal with title sponsor RBC, gave them plenty to cheer about, pulling away for his third victory of the season and 19th on the PGA Tour.
The world No. 1, from Columbia, S.C., tied for second in the Canadian Open at Glen Abbey Golf Course in 2013 and 2016.
"With my ties to Canada, Paulina and her dad being Wayne Gretzky I definitely get a lot of fans that pull for Wayne, pull for me".
"Obviously I have a lot of fans out there thanks to Wayne and the family and I appreciate all the support", said Johnson, who is married to Canadian hockey great Wayne Gretzky's daughter Paulina. "I had a lot of support this week, and it was a lot of fun".
He made the most of moving day, sizzling to a 6-under 66 during Saturday's action and mixed six birdies, two bogeys and a double bogey to close Sunday with a 70.
Johnson had been close before at Glen Abbey, finishing second in 2013 and 2016, and with this nearly assuredly being the 30th and final time Glen Abbey will host the Canadian Open, finally sealing the deal here was extra special for the World No. 1. He was never really challenged down the stretch, looking as comfortable as one can as an experienced and talented front-runner, finishing with seven birdies and the lone bogey.
"One thing I love about this game is no matter how good you are, you can get better and I'm going to continue trying to improve", Johnson said. "Unfortunately I couldn't get in the playoff".
The typically unflappable Johnson had no issues with a near two-hour weather that halted play just after he had belted his tee shot down the par-four ninth. "Hopefully I can come out tomorrow and shoot a low one".
"I needed to work on the putter though, which I did", Johnson said.
Mackenzie Hughes was the top Canadian, shooting a 68 to tie for eighth at 15 under.
But the former US Open victor warned his competitors they haven't seen his best golf yet as the US PGA Championship and FedEx Cup playoffs loom.
"It was definitely good to get off to a fast start", said Johnson.
Hamilton Golf and Country Club is hosting the tournament next year and in 2023.