Supercars teams have opted out of Wednesday's scheduled test days at Winton Motor Raceway due to wet weather.
Tickford Racing, Walkinshaw Andretti United and Brad Jones Racing all scheduled full test days for Wednesday.
The days were set to help teams find more answers with their new Gen3 cars, with the season just four rounds old.
However, rain lashed the Winton circuit area on Tuesday and Wednesday, with wet weather also affecting Tickford's rookie day on Tuesday.
All teams have since postponed their Wednesday running, some two hours after pit lane went green.
Per the Operations Manual, if a team opts to cease testing due to rain within two hours of their first lap or before 11:00am — whichever comes first — they will be deemed not to have used one of their test days.
The rule can only be used once per season.
Erebus Motorsport was also set to run its #9 Coca-Cola Camaro in a a driver evaluation day.
Erebus was going to field Super2 drivers Jay Hanson and Cooper Murray, with Will Brown also on-site.
Penrite Racing had also scheduled a rookie day for Matt Payne.
Two Super2 entries were also on-site; the Aaron Love Blanchard Racing Team Mustang, and Jack Perkins Erebus Commodore.
Red Bull Ampol Racing, Shell V-Power Racing Team, Matt Stone Racing and the Triple Eight wildcard are scheduled to test at Queensland Raceway on Thursday.
The 2023 season will resume at the betr Darwin Triple Crown on June 16-18.