Renault 'nervous' about Austin challenge

Renault admit they are wary about the stresses that Austin will place on their Formula One power units, particularly as reliability has become a chief priority over the final three Grands Prix.

Given the high mileage already accrued over the first 16 races of the 2014 season, and the blend of high-speed sections and tighter, more technical corners, Renault say they face a busy weekend in the US trying to prevent any complications or failures