Barcelona – Mercedes has shot down a rumour that the secret to its "speed" has been uncovered.
According to Auto Motor und Sport, Red Bull suspects Mercedes is able to deliver a huge power boost for qualifying because it mixes oil with fuel.
"Oil cannot be in the fuel"
Mercedes team boss Toto Wolff denies that the German marque's illegal trick has been found out.
Wolff insisted: "We've never done it.
"Even before the season starts, some teams are already seeing a lot of ghosts. It was always clear that oil cannot be in the fuel."