Red Bull boss Christian Horner believes the superior engine modes Mercedes and Ferrari are able to unleash in qualifying is the key factor preventing his team from catching its rivals.
Having made promising gains with its chassis, the Milton Keynes-based outfit has enjoyed a turnaround in form that has allowed it to get closer and even challenge main rivals Ferrari and Mercedes at recent events in Hungary, Silverstone and Austria.
The team had been lagging behind Mercedes and Ferrari at the start of the season after failing to grasp Formula One's new aerodynamic regulations, but vast improvements as the year has progressed have moved Red Bull into a much more competitive position, allowing the quadruple world champions to score a victory in Baku.