Supercars drivers had 90 minutes to learn Taupo International Motorsport Park in the weekend’s sole practice session, with Mostert driving the #25 Mobil 1 Optus Mustang to a 1:26.4937s on his final run.

In an all-Ford top three, he pipped Matt Payne after the Penrite Racing driver set a 1:26.5255s with the chequered flag out, with the Shell V-Power Racing Team’s Will Davison third on a 1:26.5445s.

PremiAir Nulon Racing’s James Golding was first of the Chevrolet contingent in fourth at 0.0933s off the pace with championship leader Will Brown fifth and 2023 champion Kostecki 12th having seemingly spent much of the session working on long-run performance.

The field had rolled out under somewhat grey skies, with the fastest first flyer being Mostert’s 1:28.6582s.

He moved the benchmark to a 1:27.8904s next time around and clocked a 1:27.5737s on his third flyer, which was soon usurped by Brown’s 1:27.3895s in the #87 Red Bull Ampol Camaro.

With those times necessarily set on new tyres, given quarantine regulations mean there is no pre-marked rubber this weekend, and a need to understand degradation, the session went into something of a lull as teams explored the track on somewhat used soft hoops.

Kostecki (#1 TFH Hire Services Camaro), on his return to Supercars, crept up to 16th at 1.0610s off the pace with a 1:28.4505s in the 26th minute, but there were few other advances.

While Kostecki was reportedly working on long-run pace, Erebus Motorsport team-mate Jack Le Brocq (#9 Camaro) raised the bar by almost four tenths of a second when he jumped from 13th to the top on a 1:27.0133s just prior to the halfway mark.

Within minutes, David Reynolds (#20 Tradie Beer Camaro) improved to third on a 1:27.5349s, which became fourth once Andre Heimgartner moved up to second on a 1:27.2445s in the #8 R&J Batteries Camaro.

Matt Stone Racing was briefly second and fourth with Nick Percat (#10 Bendix Camaro) setting a 1:27.2217s and Cameron Hill (#4 Supaglass Camaro) a 1:27.3028s in the 56th minute, before Tickford Racing’s Thomas Randle (#55 Castrol Mustang) took up third on a 1:27.2422s.

Just past the 60-minute mark, Davison (#17 Mustang) took over the ascendancy with a 1:26.9724s while Kostecki, who had just been sent on new tyres, moved up to seventh on a 1:27.3271s.

Kostecki went on with it and climbed to fourth with a 1:27.2279s on his next lap, as the track continued to rubber up.

Brad Jones Racing rookie Jaxon Evans (#12 SCT Logistics Camaro) then jumped from last to third on a 1:27.1742s, before he was pipped by Golding (#31 Camaro) on a 1:27.0942s.

It was a Dick Johnson Racing one-two in the 72nd minute when Anton De Pasquale (#11 Mustang) grabbed top spot with a 1:26.7978s.

That lasted two minutes before Triple Eight Race Engineering’s Brown bettered both with a 1:26.6121s, then Mostert split them with a 1:26.8662s and Reynolds moved into second on a 1:26.7745s.

DJR responded when De Pasquale set a 1:26.7372s and then Davison a 1:26.5445s in the 80th minute, meaning they were third and first, respectively.

Heimgartner reclaimed third with a 1:26.6558s before Matt Payne (#19 Penrite Mustang) moved into fourth in the final five minutes on a 1:26.6660s.

With less than three minutes remaining, the #25 Mustang was back on top as Mostert laid down a 1:26.4937s and Golding took over third with a minute to go.

The chequered flag came out and Payne went fastest to the second sector, despite being slower than his personal best in that sector, before completing a time 0.0318s slower than Mostert’s best.

Behind the top five of Mostert, Payne, Davison, Golding, and Brown, Heimgartner ended up sixth from De Pasquale, Evans, Reynolds, and Percat.

The latter mowed the grass at the exit of Turn 7 in an early run while Cam Waters finished 11th at just 0.2914s off the pace, with an off at Turn 11 along the way in the #6 Monster Energy Mustang.

Kostecki’s best was a 1:26.8268s at 0.3331s away from the summit, with Le Brocq 15th and Broc Feeney (#88 Red Bull Ampol Camaro) back in 21st on a 1:27.3504s.

Qualifying for Race 7 of the season, the first of the weekend, starts tomorrow at 10:20 local time/08:20 AEST, with a Top 10 Shootout to follow later in the day.

Results: Practice