Former Renault Formula 1 boss Flavio Briatore has voiced his suspicions that Red Bull duo Mark Webber and Sebastian Vettel may not be getting equal treatment this year.
Briatore, who is Webber's manager, believes that the larger than normal gap between the two drivers at Red Bull during the opening races of this season has raised his concerns.
"I hope Red Bull is a team big enough to guarantee two equal cars for its drivers, but each time something happens, it happens to Mark," Briatore was quoted as saying by Gazzetta dello Sport.
"I understand you need some luck, but if the same number comes up over and over again, it means there's a magnet under the roulette [wheel]. I'm not casting doubts over [Red Bull team principal Christian] Horner's intellectual honesty, but what's happening sounds strange.
"It would be nice for F1 to have Webber do well too, because he would be Vettel's only true challenger, and he would get the support from 90 per cent of the fans. It would be a nice duel like in [Ayrton] Senna's and [Alain] Prost's time, but back then they had equal cars, while the two Red Bulls instead may be equal only in their colours."
Red Bull Racing has long denied any suggestion of favouritism towards Vettel, and in the last event in Spain it was the German's KERS that failed in qualifying.
Briatore also suggested that Vettel may not be as good as other drivers on the grid - despite his strong start to the campaign.
Speaking about Fernando Alonso and Lewis Hamilton, Briatore said: "They're the best drivers. I wonder what they would do at the wheel of the Red Bull. Maybe they'd lap everyone else.
"Vettel is doing a good job, he doesn't make any mistakes and if he carries on this way the championship will be over in two or three races. But then, it's no secret that Red Bull has the best designer around. Adrian Newey is the [Leo] Messi of F1 engineers."