OAKVILLE, Ont. -- Dustin Johnson pulled away from the field after a nearly two-hour rain delay to win the RBC Canadian Open for the first time.

Johnson shot a 6-under 66 to finish the only Canadian stop on the PGA Tour at 23-under par.

The world No. 1 tied for second in the Canadian Open at Glen Abbey Golf Course in 2013 and 2016.

Byeong Hun An (69) and Whee Kim (69) finished as runners up at 20-under in the US$6.2 million event, with Keegan Bradley (64) placing fourth at 19-under.

Mackenzie Hughes (68) of nearby Dundas, Ont., was the low Canadian, tying for eighth at 15 under overall.

A Canadian has not won the national title since Victoria's Pat Fletcher accomplished the feat in 1954.

Johnson entered the day in a four-way tie for the lead with Kim, Hun An and Kevin Tway but had seven birdies and a bogey to pull away from the group.

A nearby lightning storm delayed play for an hour and 45 minutes and shrunk the massive crowd that usually trails Johnson from hole to hole.

Golf Canada CEO Laurence Applebaum thought Johnson's victory was an appropriate sendoff for Glen Abbey. The Jack Nicklaus-designed golf course has been slated for redevelopment by ClubLink, the property's owner.

"This event has been one of our best ever," said Applebaum. "Started at the front of the week with Triple Crown winner Lee Trevino showing up for the Hall of Fame, and then the field we had. DJ, four of the five U.S. Open combatants, Bubba Watson, and the great Canadian roster.

"And then our world No. 1 showing his class, makes for a spectacular finish."

Hamilton Golf and Country Club will host the 2019 Canadian Open. It is also shifting forward in the PGA Tour's schedule, moving to early June in the week before the U.S. Open.