OAK Racing led a P2 sweep of the top three positions in opening practice for Sunday’s Mobil 1 Sportscar Grand Prix at Canadian Tire Motorsport Park.

Gustavo Yacaman pedaled the No. 42 Morgan-Nissan to a best lap of 1:10.928 early in the 60-minute session.

Yacaman’s quick time edged out the pair of Extreme Speed Motorsports HPD ARX-03bs, which were second and third on the time charts.

Ryan Dalziel was quickest of the ESM entries with a 1:11.277 lap, while Johannes van Overbeek recorded the quick time aboard the No. 2 entry, which was third.

The No. 5 Action Express Racing Corvette made a late session improvement to fourth, with Christian Fittipaldi reeling off a 1:11.322 lap to go quickest of the DP contenders, while Richard Westbrook’s No. 90 Spirit of Daytona Racing machine completed the top-five overall and in class.

The ever-improving DeltaWing Coupe posted the sixth quickest time overall, thanks to a 1:11.561 lap by Andy Meyrick.

GT Le Mans was led by BMW Team RLL’s John Edwards, who clocked a 1:16.019 lap time in his No. 56 BMW Z4 GTE.

Edward’s time eclipsed the No. 91 SRT Motorsports Dodge Viper SRT GTS-R of Dominik Farnbacher by 0.020 seconds, with the No. 3 Corvette C7.R of Jan Magnussen making it three different manufacturers in the top-three.

Spencer Pumpelly, meanwhile, was quickest in GT Daytona, leading an Audi 1-2-3 in class.

The Flying Lizard Motorsports driver reeled off a 1:19.679 lap time to edge out the No. 48 Paul Miller Racing R8 LMS of Christopher Haase by 0.097 seconds.

The session only saw one red flag, which came early on for the No. 48 Fall-Line Motorsports Audi, which stopped on track.

Friday’s second and final practice session is on tap for 4:05 p.m. ET.

RESULTS: Practice 1