The #6 Monster Energy Mustang pilot finished the 40-minute session with a best time of 1:13.9603s, 0.1206s clear of team-mate Thomas Randle.

Supercars Championship leader Will Brown ended up third at another 0.0813s back in the #87 Red Bull Ampol Camaro, ahead of the Blanchard Racing Team’s James Courtney and Penrite Racing’s Matt Payne.

Almost all of the eventual top 10 set their respective fastest laps on their first runs around the Reid Park Street Circuit, where teams must only hand back one set of new tyres at the end of practice proceedings later today.

The field had rolled out in overcast conditions and Waters laid down a 1:14.6950s before Randle (#55 Castrol Mustang) pushed the benchmark to a 1:14.0809s next time around.

Waters then reclaimed the ascendancy with that 1:13.9603s on his third hot lap and no one would go any faster.

Triple Eight Race Engineering’s Brown likewise sat third for the vast majority of the session, with Courtney (#7 Snowy River Caravans Mustang) fourth on a 1:14.2128s and Grove Racing’s Payne fifth on a 1:14.2159s.

Andre Heimgartner was the first of three Brad Jones Racing drivers in the top 10, taking sixth with a 1:14.2439s in the #8 R&J Batteries Camaro, with team-mates Bryce Fullwood (#14 Middy’s Camaro) eighth and Macauley Jones (#96 Pizza Hut Camaro) rounding out a top 10 covered by 0.4178s.

The Shell V-Power Racing Team’s Anton De Pasquale (#11 Mustang) was one of very few to go faster after his first run, claiming seventh with a 1:14.3054s, while Erebus Motorsport’s Brodie Kostecki (#1 Erebus Camaro) ended up ninth on a 1:14.3390s.

Notables further back included Broc Feeney (#88 Red Bull Ampol Camaro) in 13th at 0.4857s off the pace and Chaz Mostert (#25 Mobil 1 Optus Mustang) in 15th at 0.5817s away from top spot.

The session ran green throughout, with windy conditions, but sprinkling rain only started to fall as drivers came in at the conclusion of proceedings.

There were few notable incidents, with Mostert venturing into the dirt at Turn 6 at one point, Jones touching the wall on drivers’ left at turn-in at Turn 3, and Payne and Courtney separately running long at Turn 11.

A number of drivers did report steering rack issues, however, with Matt Stone Racing’s Cameron Hill (#4 PPQ Camaro) missing more than 30 minutes due to the drama.

Practice 2 for the Repco Supercars Championship field, another 40-minute session, starts this afternoon at 15:10 local time/AEST.

Results: Practice 1