Red Bull's appeal against Daniel Ricciardo's disqualification from the Australian Grand Prix could determine the success of Formula 1's new fuel regulations.
While the Australian's second place is at stake, insiders at rival teams have suggested the outcome of the appeal could have far wider implications for the future of F1's new rules.
If Red Bull does successfully prove to the International Court of Appeal that it was right to ignore the FIA's own fuel flow sensor readings in favour of its own data, then it could open the way for teams to effectively railroad through the policing of fuel limitations at will.
One high-level source at a frontrunning team said that if teams are allowed to ignore the FIA's reading of the two key fuel limits imposed - the 100kg limit per race and the 100kg/h fuel-flow limit - then the very essence of F1's new efficiency regulations will be blown apart.
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That would open the way for a farcical situation where the outcome of grands prix would be decided not on post-race inspections in parc ferme, but in lengthy court proceedings where teams would be arguing how accurate their own fuel data was.
And while there is an ongoing debate about the accuracy of the fuel-flow sensors used to monitor what teams are up to, the FIA's confidence that the precision is good enough has to be accepted by all if F1's new regulations are to work.
FIA HAS FINAL SAY ON ACCURACY
F1 race director Charlie Whiting said ahead of the Australian Grand Prix that the governing body was satisfied with the Gill Sensors-supplied components.
And he made it clear that the FIA was open to allowing teams to use their own fuel data if its technical staff believed the sensor was out.
"We monitor them all the way through the race and, if we see a fault, we have a fallback solution," he said.
"We know, for example, what the fuel used at the end of lap 24 was. And that will be the starting point for our new calculation. So we are in good shape there."
Exact procedures for the circumstances under which teams would be allowed to rely on their own data rather than faulty FIA fuel sensor equipment was laid down in a technical directive sent to them on March 1.
And it was emphasised then that it would be wholly at the FIA's full jurisdiction as to when those back-up readings could be used.
The sport's competitors could not decide for themselves when to rely on their own data and ignore what the governing body was saying.
It is no different to the need to rely on the FIA weighbridge readings on a grand prix weekend, even if they do not tally exactly with a team's own readings.
Just as teams have to trust that the FIA polices the technical regulations rigorously when it comes to ruling on the compliance of all their rivals, so the success of the fuel-flow regulations relies on the governing body ensuring that all the sensors are equally reliable and accurate.
There are still details of this case that have yet to emerge, such as how inaccurate Red Bull believed the FIA sensor to be, and just how much above the fuel-flow rate the FIA reckoned the team to have been.
But while they may matter to this specific case and decide the final result of the Australian GP, it is where the ruling leaves the policing of F1's fuel efficiency formula that is a more serious concern to everyone else right now.