Mercedes tore into Formula One rival Red Bull at an appeals court hearing on Monday over the disqualification of Daniel Ricciardo at the Australian Grand Prix, saying the team flouted rules and must be shown a "yellow card" to stop it from becoming a repeat offender.

The court said they expected to deliver their ruling by Tuesday morning. In their appeal, Red Bull argued that race officials should not have stripped Ricciardo of his second-place finish, and the 18 points that go with it, for breaching F1's new rules on fuel usage.

The case represented the first major challenge to this season's sweeping rule changes, which have seen F1 ditch 2.4-liter, V8 engines for smaller 1.6-liter, V6 turbo hybrid engines.

The rules are forcing teams to be more fuel efficient, allowing them to burn no more than 100 kilograms per race, about one third less than the V8s used. The rules also limit the rate at which fuel is burned to no more than 100 kilograms per hour at any time.

Red Bull were accused of consistently overstepping that mark with Ricciardo's car in the season-opening race on March 16 in Melbourne. Governing body FIA told Red Bull during the race that Ricciardo's car was burning through fuel too quickly. The team dialed back the flow for a few laps. But after that slowed Ricciardo, Red Bull then turned his engine back up again.

Red Bull argued to motorsport's Paris-based tribunal for resolving disputes, the International Court of Appeal, that the FIA-approved sensor used to measure the delivery of fuel to Ricciardo's car was faulty and so the team relied instead on its own fuel-flow measurements.

Representing Red Bull, lawyer Ali Malek said Ricciardo's fuel sensor was "obviously unreliable," his disqualification based on a "flawed and incorrect" interpretation of F1 rules and that the team was perfectly entitled to use its own fuel-flow calculations.

Mercedes lawyer Paul Harris argued that Red Bull was in "flagrant breach" of F1 rules. He said the court should impose an increased but suspended penalty on Red Bull to dissuade the team from any further rule violations.

"We are frankly, and with great respect, concerned that Red Bull have shown such a flagrant and deliberate disregard for these rules," Harris said. "There is a real risk that they will do it again. We must have a level playing field," he added. "We respectfully submit, gentlemen, that the most effective way of ensuring that Red Bull do not flout further written and oral instructions from the FIA for at least the remainder of this season is for this court to recognize the severity of their infringement and to impose a further sanction upon them."

Harris accused Red Bull of knowingly and repeatedly ignoring instructions from FIA official Fabrice Lom to turn down the fuel flow to Ricciardo's engine, because the team did not want to slow the Australian driver.

"They knew they were not complying with the technical directives, they knew they weren't doing what Mr. Lom had said repeatedly and they knew full-well that it was being done in order to obtain an express sporting advantage - 0.4 seconds per lap for Mr. Ricciardo," he said.

Harris said FIA-approved sensors that teams use to measure their rates of fuel usage are "rigorously tested and rigorously calibrated." He also argued that Red Bull's own alternative system which the team used to measure Ricciardo's fuel use is "not 100 percent accurate."

"Red Bull thinks it is entitled to pick and choose between the measurements whenever it suits Red Bull," Harris said.

Harris also asked: If FIA allows Red Bull not to follow instructions on fuel flow, "then what is to stop a team ignoring the FIA when it comes to other measurement systems, for instance the weight of the car?"

Other teams "could also with impunity ignore technical directives and instructions from the FIA," Harris said. "That must be wrong."
FIA lawyer Jonathan Taylor argued that the "essence" of sport is that all competitors abide by the same rules.

"A team cannot pick and choose," he said.

Red Bull confirmed that it initially turned down the fuel for Ricciardo, because Lom asked it to. But after that affected Ricciardo's performance, Red Bull engineers decided to turn the fuel rate back up again.

Much of the hearing was taken up with detail about the accuracy and reliability of the sensors, how engine temperature and other factors might impact the readings, and how their accuracy compares with alternative, computer-generated fuel-flow measurements that Red Bull used.