The German car manufacturer endured another difficult weekend in Miami as struggles in practice and qualifying were followed by more encouraging pace in the race.
The team has admitted, however, that this rollercoaster of form that the W14 has demonstrated has left it unable to understand exactly what has gone wrong.
For the next race at the Emilia Romagna Grand Prix, Mercedes is introducing a major update, which will include changes to the sidepod, floor and front suspension.
And while the team hopes that the new package will deliver a step forward in form, more critical, reckons boss Toto Wolff, is the way that the …