Michael Schumacher's podium finish in the European Grand Prix is under investigation after the German was summoned to see the stewards to explain why he used his DRS in a yellow flag zone at the end of the race.
Schumacher secured the first top three finish since he returned to F1, but he may not keep the result if the stewards deem that he was wrong to have used the DRS in the closing stages of the race while yellow flags were out.
Sebastian Vettel was penalised for using DRS under yellow at the Spanish Grand Prix earlier this year.
Mark Webber, who finished right behind Schumacher on the road, complained about his Mercedes rival's actions - and Red Bull Racing team boss Christian Horner said he hoped the stewards would take action over the matter.
"I am sure the stewards are having a good look at it, because if you look at it, it is pretty clear," explained Horner. "Mark was very vocal on the radio that Michael had used the DRS and there is very clearly a yellow flag on the right hand side once Michael had it open.
"We know from bitter experience that you are not allowed to use it. Seb had a drive through in Barcelona, so it is really up to the stewards."
Although video evidence suggests that Schumacher's DRS was open when yellows were out, sources suggest that the German driver had actually slowed for the warning flags as is requested by the regulations.