Michael Cooper led a Cadillac 1-2 in practice for this weekend’s Pirelli World Challenge round on the streets of St. Petersburg.

The GT class rookie reeled off a best lap of 1:12.965 in his No. 8 Cadillac ATS-V.R in Thursday’s one-and-only official practice session, outpacing teammate and four-time series champion Johnny O’Connell by 0.446 seconds.

Jon Fogarty, in his first appearance on the 14-turn 1.8-mile street circuit, was third quickest in the No. 99 GAINSCO/Bob Stallings Racing McLaren 650S GT3.

The No. 9 K-PAX McLaren of Alvaro Parente and Bryan Heitkotter’s No. 05 Always Evolving Nissan GT-R NISMO GT3 completed the top-five overall and in the GT class in the 50-minute session.

GTA was led by the No. 07 Scuderia Corsa Ferrari 458 Italia GT3 of Martin Fuentes, who recorded a 1:14.011 lap that put the double COTA winner 13th on the overall time sheets.

Sloan Urry, meanwhile, led the GT Cup class thanks to a 1:16.498 in the No. 20 TruSpeed Autosport Porsche 911 GT3 Cup car.

Championship rival Alec Udell crashed his No. 17 GMG Racing Porsche into the Turn 1 barriers, which brought out the only red flag of the session.

No other significant incidents were reported.

Qualifying for GT/GTA/GT Cup is next up and is set for Friday at 9:35 a.m. ET.