If the first TUDOR United SportsCar Championship practice session is any indication of what to watch out for at the Circuit of the Americas this weekend, GTLM competitors better watch out for the Porsche North America team.

The three Porsche 911 RSRs swept the top spots in the opening practice for this weekend’s Lone Star Le Mans.

Frederic Makowiecki and Patrick Pilet’s #910 Porsche was the quickest of the three with a lap time of two minutes and 4.844 seconds

Teammates Patrick Long and Michael Christensen were second fastest, stopping the clocks at two minutes and 5.102 seconds aboard their #912 Porsche and Nick Tandy and Jorg Bergmeister were third with a lap of two minutes and 5.230 seconds.

The Dodge Viper SRT of Jonathan Bomarito and Kuno Wittmer and the BMW Z4 GTE of Bill Auberlen and Andy Priaulx rounded out the top 5.

Championship leader Antonio Garcia and teammate Jan Magnussen at Corvette Racing ended the first practice session in ninth.

In the Prototype class, Michael Valiante and Richard Westbrook of Spirit of Daytona Corvette DP topped the timing charts registering a fastest lap of two minutes and 0.306 seconds.

Other class leaders were PR1/Mathiasen Motorsports drivers Frankie Montecalvo and Gunnar Jeannette in the PC class and the TRG-AMR machine of Al Carter and James Davison in GTD.

TUDOR Championship teams will be back in action 9:00 am local time, Friday, September 19 for Practice 2.

Top three in class (overall in parentheses)

(1) #90-P Richard Westbrook (Corvette DP) 2:00.306

(2) #60-P Oswaldo Negri (Ford EcoBoost/Riley) 2:00.387 (0.081-)

(3) #5-P Joao Barbosa (Corvette DP) 2:00.809 (0.503-)

(8) #52-PC Gunnar Jeannette (Oreca FLM09 Chevrolet) 2:02.453 (2.147-)

(9) #08-PC Jack Hawksworth (Oreca FLM09 Chevrolet) 2:02.584 (2.278-)

(10) #09-PC Bruno Junqueira (Oreca FLM09 Chevrolet) 2:02.752 (2.446-)

(18) #910-GTLM Patrick Pilet (Porsche 911 RSR) 2:04.844 (4.538-)

(19) #912-GTLM Patrick Long (Porsche 911 RSR) 2:05.102 (4.796-)

(20) #911-GTLM Nick Tandy (Porsche 911 RSR) 2:05.230 (4.924-)

(33) #007-GTD James Davison (Aston Martin V12 Vantage) 2:09.815 (9.509-)

(34) #27-GTD Andrew Davis (Porsche 911 GT America) 2:10.055 (9.749-)

(35) #300-GTD Dane Cameron (BMW Z4) 2:10.217 (9.911-)