Tied for third-round lead with Kevin Tway, Byeong Hun An and Whee Kim, Johnson shot a 6-under 66 for a three-stroke victory over Kim and An.
"I like the golf course, my game is in really good form, I have a lot of confidence in it but I'm going to have to go out and play really well tomorrow".
Johnson, who posted a final round six-under 66 to get to 23-under, finished three shots clear of South Korean pair Whee Kim and Byeong Hun An on his way to becoming the second three-time victor this season (Bubba Watson is the other). "I've got a great family, with a lot of support from them and then obviously a great team to help me to get to where I'm at". "I just did not score very well at Carnoustie at all".
He said Saturday he would need to play the par 5s better if he wanted to hoist the trophy and on Sunday he birdied all four.
It fell into place at Glen Abbey, the Jack Nicklaus-designed course slated for redevelopment.
With his challengers off to a shaky start Johnson seized control, opening up a three-shot lead through four holes. I just scored really badly.
Even though the big prizes have evaded him this year so far, top-ranked Dustin Johnson still is having a superb season on the PGA Tour.
But the American's charge stalled as he struggled with his putter and he had to settle for five consecutive pars before rolling in a 12-footer at the eighth. But he plummeted 42 spots down the leaderboard Sunday, and finished with a double bogey on No. 18, eliciting a groan from the crowd when he hit the ball into the water. He also won the Sentry Tournament of Champions in January and the FedEx St. Jude Classic in June.
When play resumed following a almost two-hour delay, the gap tightened as Johnson recorded a par and An and Kim picked up birdies to cut American's lead to two.
Keegan Bradley carded the round of the day, an eight-under 64 which included an eagle two and a birdie-birdie-birdie finish, to jump up to lone fourth. Teryn Schaefer presents the best social media posts from around the world of golf in "Good, Bad & Unusual" and after each day's play brings you the biggest talking points in "The Takeaway".
"But, unlike maybe (Friday) where I was probably a bit impatient at times, I just told myself I was playing well and had some chances coming in and kind of got hot there". "But I was, like, 'This is very chip-in-able and if I do it with the jersey on, it's way cooler'".
Hughes, with wife Jenna and nine-month-old son Kenton watching on, began the day in a tie for 13th, and climbed up to fifth before a bogey on 15.
Saturday's third round, the proverbial "Moving Day" as it were, provided some significant separation at the top of the leaderboard: There was a four-way tie for first place at 17-under par featuring Kim, Tway, Johnson, and An.