Tommy Milner took control of the opening practice session for this weekend’s Michelin GT Challenge at Virginia International Raceway as the American pushed the No. 4 Corvette Racing C7.R to a lap of 1m42.341s around the 3.2-mile road course.

The yellow Corvette edged the No. 67 Ford Chip Ganassi Racing GT driven by Richard Westbrook (+0.103s) and the returning Risi Competizione Ferrari 488 piloted by Giancarlo Fisichella (+0.175s) during the one-hour session.

Mild dramas were recorded for the No. 67 Ford as a transmission leak kept the car on pit lane. Initial plans to send the GT back to the paddock for repairs, which would have ended its running prematurely, were scrubbed. Westbrook duly turned his fastest lap while living with the leak.

The gap from Milner to the ninth-place GT Le Mans entry from BMW Team RLL was 1.049 seconds.

GT Daytona’s field of 16 cars was led by Change Racing’s Jeroen Mul in the No. 16 Lamborghini Huracan GT3, whose lap of 1m44.700s was impressively close to the best GTLM had to offer. Mul was followed by Andrew Davis in the No. 57 Stevenson Motorsports Audi R8 LMS (+0.203s) and Christina Nielsen in the no. 63 Scuderia Corsa Ferrari 488 GT3 (+0.332s).

Fourth-place Patrick Lindsey in the No. 73 Park Place Motorsports Porsche 911 GT3 was the only GTD driver to encounter issues when he suffered a flat tire and crept around the sprawling circuit on the way to pit lane.

The GT-only IMSA WeatherTech SportsCar Championship event, featuring 25 production-based cars across both classes, is the last of its kind this season.

UP NEXT: FP2, 4:10 p.m. ET