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

Christian Horner, the longest-tenured team principal in Formula 1, is out after two decades. Here's what he told the team.

With Fred Vasseur facing intense scrutiny over his future as the Ferrari team boss courtesy of the Italian press, Horner had championed the need for “stability” in an organisation, stressing Red Bull enjoyed it and it has led to 14 world championships. Just days later, Red Bull suddenly released Horner with immediate effect, the memo not received.