Olivier Pla has set the fastest time in the opening practice session for the Sahlen’s Six Hours of the Glen.
The Frenchman piloted the #60 Meyer Shank Racing Acura ARX-05 to the top spot on the timing sheets by posting a 01:31:056.
He would go over half a second quicker than the #31 Whelen Engineering Cadillac DPi-VR of Mike Conway, with Renger van der Zande third in the #01 Chip Ganassi Racing Cadillac DPi-VR.
Alexander Rossi, inserted into the line-up for the #10 Wayne Taylor Racing Acura ARX-05, went fourth quickest, with the top five rounded out by Loic Duval’s #5 Mustang Sampling Cadillac.
Harry Tincknell went sixth in the #55 Mazda RT24-P, with Kamui Kobayashi seventh for Ally Cadillac Racing.
In LMP2, former Mazda driver Tristan Nunez led proceedings as he lapped Watkins Glen International in 01:33:386 behind the wheel of the #11 WIN Autosport ORECA 07-Gibson.
Nunez outpaced the #8 Tower Motorsport ORECA of John Farano by just 0.045s, with Scott Huffaker third for PR1/Mathiasen Motorsports.
LMP3 was led by the #36 Andretti Autosport Ligier JS P320, with Oliver Askew’s 01:40:812 leading Jon Bennett’s #54 CORE Autosport Ligier by 0.083s.
Felipe Fraga led Riley Motorsports team-mate Dylan Murry into third and fourth in class respectively.
Corvette Racing topped GTLM one-two in the opening session for the six-hour enduro as the #4 Corvette C8.R of Nick Tandy posted a 01:42:517.
Tandy was 0.157s quicker than team-mate Antonio Garcia in the #3 sister car, while the two BMWs of Jesse Krohn and Philipp Eng came in third and fourth.
Matt Campbell rounded out the class in the #79 WeatherTech Racing Porsche 911 RSR-19, 1.698s off the fastest time in class.
Finally, Jack Hawksworth led GTD in the #14 Vasser Sullivan Lexus RC F GT3, as the Briton’s 01:46:673 was 0.188s faster than Patrick Long in the #16 Wright Motorsports Porsche 911 GT3 R.