Engine Rules Block Mercedes From Giving Russell Its New Power Unit Upgrade in Singapore

George Russell's already painful start to the flyaway stretch has grown worse. Mercedes has confirmed the Briton will begin this weekend's Singapore Grand Prix from the back of the grid after his engine failure at Sepang last weekend pushed him beyond his permitted power-unit allocation. The team had hoped to soften the blow by fitting its new ADUO1 engine upgrade at Marina Bay, but Formula 1's regulations stopped the plan cold. Power-unit manufacturers must offer any upgrade to their customer teams at the same time the factory squad receives it, and Mercedes simply could not build and homologate enough of the new units in time. According to reporting by Sky Sports Italy, the shortage centered on the turbocharger, leaving McLaren, Alpine and Williams without the required simultaneous supply. The earliest the ADUO1 unit can now appear is the United States Grand Prix at the Circuit of the Americas on October 23-25, meaning Russell and Mercedes must decide whether to swallow a second consecutive back-of-grid penalty to add it to his pool. Austin's layout should offer far better overtaking chances than Marina Bay, where overtaking is notoriously difficult and this year's debut Sprint leaves teams with only a single practice session. The FIA granted Mercedes its sole in-season engine upgrade after judging its internal combustion engine to be between two and four percent short of Red Bull's benchmark.