MISSISSAUGA, Ont. -- Late in the first quarter Wednesday night, Canadian basketball phenom R.J. Barrett veered around a Ryerson defender to throw down an emphatic dunk.

He and teammate Zion Williamson celebrated with a chest bump that was almost as big.

Consider it Barrett's college coming-out party.

Making his Duke debut in his virtual backyard, the electrifying 18-year-old from Mississauga, Ont., made his first game in a Blue Devils jersey a memorable one, scoring a game-high 34 points in a 86-67 pre-season victory over Canadian university's Ryerson Rams.

Williamson added 29 points and 13 rebounds. The two young stars took a seat with three minutes to play. JV Mukama led Ryerson with 20 points and 12 rebounds.

NCAA rules permit teams to take an international trip once every four years, and the Blue Devils opted to head north for the first time in the program's history. They'll play the University of Toronto on Friday, then head to Montreal to face McGill on Sunday.

Fans were eager to catch a first glimpse of not only Barrett -- the presumptive No. 1 pick in next spring's NBA draft -- but Duke's top-ranked freshman class that includes Williamson and Cam Reddish, who are ranked Nos. 2 and 3 behind their Canadian teammate. Both games at the Paramount Fine Foods Centre sold out quickly. Wednesday's affair was being streamed on ESPN, and drew a media contingent several-dozen strong.

Wednesday's pro-Duke crowd included Portland sharpshooter and fellow Mississauga native Nik Stauskas and 10-time NBA all-star David Robinson.

Barrett is already being touted as perhaps the greatest player to come out of Canada. The six-foot-seven swingman won both the Gatorade Player of the Year and Naismith Player of the Year last season to help Florida's Montverde Academy to an undefeated season and coveted U.S. high school title. He also led Canada to its historic gold medal at the 2017 U19 world championships.

The Rams, back-to-back Canadian university silver medallists, held their own against one of the NCAA's most prominent teams. The Rams led 17-15 to end the first quarter, and Tanor Ngom, a Senegalese sophomore, ignited the crowd with a huge dunk over Duke's Alex O'Connell early in the game.

The Blue Devils, who Hall of Fame coach Mike Krzyzewski pointed out had practised less than a dozen times together before the tour, starting rolling in the second,

Late in the second quarter, Williamson showed his size-defying athleticism when he scored on a huge putback dunk, bringing the fans out of their seats. One sarcastic fan hollered "Show us something, Zion!" At six foot seven and 285 pounds, Williams is an enigma. He could easily be mistaken for a college football rookie, yet has the leaping abilty of a high jumper, breaking the Duke record with his eye-popping 45-inch vertical leap in team testing.

The Blue Devils took a 40-28 advantage into the halftime break, and led 65-48 with one quarter left to play.

Duke was technically the home team, despite the proximity of Ryerson's downtown Toronto campus, and the capacity crowd -- an arena sellout is listed at about 5,400 -- was a sea of Duke blue. Tables on the arena concourse were selling special edition Duke Canada Tour T-shirts. Video footage of Duke's boat tour of Toronto Harbour from earlier in the week was shown during a timeout.

And an hour before opening tipoff, a long lineup of Blue Devils fans stretched down the sidewalk of what was formerly the Hershey Centre, eager to get the first glimpse of this season's squad and its homegrown Canadian star.

Duke is fourth in NCAA all-time wins, while Krzyzewski is the NCAA's all-time winningnest coach with five NCAA titles. He also led the U.S. men's national team to six gold medals.