A Red Bull complaint about McLaren's rear wing appears to have paid off, with the championship challengers being told they are no longer allowed to use the wing design used at the Azerbaijan Grand Prix.
A viral social media clip, that has been viewed over seven million times, showed some flexibility in McLaren's rear wing design in Baku as Oscar Piastri attempted to defend from Charles Leclerc.
At the Singapore GP, the FIA confirmed that McLaren's car design was legal and passed all stationary checks following a car inspection.
However, McLaren have now been told that they cannot use the wing design again this season.
McLaren wing banned
In a huge boost for Red Bull's championship hopes, it appears their complaints against McLaren have yielded the desired result, although the Woking-based outfit will not receive a points deduction due to the FIA technically ruling the design as legal.
McLaren were told on Thursday evening at the Singapore GP that they would not be able to use it, with the design reportedly giving them 'one to two tenths' of performance at tracks such as Baku.
McLaren were not planning to use the wing in Singapore, or at any of the next three races on the calendar, with those few tracks requiring wings with more downforce that are constructed completely differently.
However, McLaren would likely have used the wing design at the upcoming Las Vegas GP, a track that is known for its high-speed sections.
In an official statement, McLaren said: "While our Baku rear wing complies with the regulations and pass all FIA deflection tests, McLaren have proactively offered to make some minor adjustments to the wing following our conversations with the FIA.
"We would also expect the FIA to have similar conversations with other teams in relation to the compliance of their rear wings."
McLaren passed all stationary tests from the FIA, but the design's flexible nature is only likely to become apparent on very long straights, such as the home straight on the Baku circuit where the viral social media clip was captured.