A late charge from Matt Campbell propelled Porsche to the top of the timesheets in opening free practice for Sunday’s Austin round of the World Endurance Championship.
The Australian found almost exactly a second aboard the #5 Penske-run factory Porsche 963 LMDh as the chequered flag was being unfurled at the end of the 90-minute session on Friday afternoon.
Campbell posted a 1m53.574s to go nearly half a second clear of the next best in the Hypercar class around the 3.43-mile Circuit of The Americas.
Robert Kubica ended up second on 1m54.034s with a lap aboard the AF Corse-run customer Ferrari 499P Le Mans Hypercar that stood as the fastest time for the majority of Free Practice 1.
The Polish driver went quickest after a short red-flag stoppage following a breakdown of communications in race control, knocking factory Ferrari driver Antonio Fuoco off the top spot.
Fuoco ended up fourth in the times after his 1m54.118s was bettered by Oliver Rasmussen with a 1m54.051s in the best of the privateer Jota team’s Porsche 963 and then by Campbell’s factory car.
Antonio Giovinazzi improved to fifth at the end of the session in the second of the factory Ferraris with a 1m54.186s.
The late improvements from Campbell and Giovinazzi pushed Earl Bamber down to sixth in the solo Cadillac V-Series.R LMDh in which he posted a 1m54.262s.
The championship-leading Porsche Penske Motorsport entry took seventh in the times, Kevin Estre setting a 1m54.276.
Rene Rast was top WRT BMW driver with a 1m54.286s good enough for eighth position, while the sister M Hybrid V8 was ninth in the hands of Marco Wittmann on a 1m54.510s.
Tenth place and the first car more than a second off Campbell’s chart-topping pace as the best of the Toyota GR010 HYBRID LMHs in which Nyck de Vries set a 1m54.620s.
Lamborghini was the next best manufacturer in 12th following a late improvement from Daniil Kvyat aboard the solo Iron Lynx-run SC63 LMDh.
The two Alpine A424 LMDhs took 13th and 14th in the hands of Mick Schumacher and Charles Milesi and the two Peugeot 9X8 2024 LMHs were 16th and 17th with times set by Stoffel Vandoorne and Mikkel Jensen.
Ferrari was quickest in LMGT3 courtesy of a 2m06.253 was Alessio Rovera in the best of the AF Corse-run 296 GT3s.
That gave him a margin of two-tenths over Dennis Olsen in the best of Proton Competition’s Ford Mustang GT3s.
He posted a 2m06.475s, which was three-tenths faster than Ben Barker in the sister Mustang.
The two TF Sport Chevrolet Z06 GT3.Rs took fourth and fifth in class, Charlie Eastwood ending up three hundredths quicker than team-mate Daniel Juncadella.
The two Manthey Porsche 911 GT3-Rs that sit atop the LMGT3 points classification were only 16th and 18th in the times.
Second free practice for Sunday’s Lone Star Le Mans six-hour race starts at 17:10 local time.