Lewis Hamilton's victory in the Italian Grand Prix was under investigation on Sunday after his Mercedes team were alleged to have raced with illegally low tyre pressures. Mercedes were summoned to explain the issue by racetrack stewards leaving the result in suspense.
The newly-blond defending two-time world champion, who had produced a flawless drive on his way to a consummate victory by 25 seconds, said he knew nothing of the controversy, which erupted during the post-race ceremonies conducted by Star Wars film director George Lucas, who interviewed the top three finishers on the victors' podium.
Hamilton's win had, at least provisionally, given him a luxurious 53-points lead over his nearest championship rival and Mercedes team-mate Nico Rosberg in the drivers' title race.
The German retired with a blown engine with two laps remaining while running in third place and chasing second-placed Ferrari driver Sebastian Vettel. Both Hamilton and Rosberg's cars and tyres were under investigation.
The technical delegate Jo Bauer's report claimed that Hamilton's left rear tyre was 0.3 psi below the required pressure and Rosberg's was 1.1 psi below when their tyres were checked on the grid before the race.