According to Dutch commentator Nelson Valkenburg, many Red Bull staff members were upset by Christian Horner’s decision last year to renew Sergio Perez’s contract despite his poor results, but now his closest allies are reportedly "very unhappy" since he’s no longer in charge.

By sacking Christian Horner, Red Bull has made a big change to try to return to F1 winning ways. But there are other steps it must take, too