Racing Point should get away with fielding its 'pink Mercedes' in 2020, according to former F1 driver Ralf Schumacher.
The Lawrence Stroll-owned team, which will become Aston Martin next year, says it is "extremely disappointed" that Renault lodged a formal protest about the legality of the car after last Sunday's race in Austria.
Red Bull, while not joining the protest, is apparently supportive of the move.
"I think everybody is worried about the Racing Point," said team boss Christian Horner.
"Perez was three or four tenths quicker than Bottas at one point."
But Racing Point said Renault's argument - that parts of the car are illegal copies of last year's title-winning Mercedes - is "misconceived and poorly informed".
The FIA has seized parts of Racing Point's braking system for analysis, and they will be compared to corresponding parts from last year's Mercedes to determine if any 'listed parts' have been improperly shared.
"I think Renault's protest is clever as it focuses on a component that is extremely difficult to copy on the basis of photographs alone," said Ossi Oikarinen, an expert for the Finnish broadcaster C More.
"Copying is quite normal in F1, but if you don't do your own development work, that is against the rules," he explained.
"If you take last year's Mercedes and put it on the track, that saves you a lot in development costs and is unfair. When you think it is about the constructors' championship, we're talking about millions."
However, Schumacher actually applauds Racing Point's strategy.
"In the current situation, modern Formula 1 must allow these things for the smaller teams," he told Sky Deutschland. "It is much more efficient.
"It's the only way small budgets will be possible again. This way, Racing Point has a chance to be in the top five, which I think is great.
"Honestly, I cannot understand Renault's anger. They have everything they need to simply build a better car," Schumacher added.