Helmut Marko has reportedly pushed against Christian Horner's massive power within Red Bull Racing. Horner, the former team principal of Red Bull, held multiple avenues within the Austrian team, and Marko, the advisor to the same team, wanted to curb his excessive power.
Marko and Horner were at the centre of power in Red Bull Racing for two decades. While the former carried out his duties as an advisor, the latter was the team principal. However, Marko only had the advisory role, but Horner flexed his muscle beyond his role as a team principal.
As a result, this was not seen in a welcoming manner by many within the team, including Marko. According to a recent report by The Race, Marko was one of the prime figures to push back against Horner for having too much power in Red Bull.
Moreover, Helmut Marko is also quite close to Max Verstappen, the star driver for the Austrian team, as well as his camp that includes his father, Jos Verstappen and manager, Raymond Vermeulen. Interestingly, Verstappen Sr. is not a huge fan of Horner, and this is widely known in the F1 fraternity.
In addition to this, Marko also brought in changes to Max Verstappen's contract clause that allowed the Dutchman to leave Red Bull if the former is sacked. In doing so, Marko safeguarded his position in the Milton Keynes-based team.
Christian Horner let his feelings known on sudden dismissal
Christian Horner shared his thoughts after Red Bull dismissed him with immediate effect. Addressing the team back at their factory in Milton Keynes, here's what the British boss said:

"Yesterday I was informed by Red Bull that, operationally, I will no longer be involved with the business or the team moving forward from after this gathering. I will still remain employed by the company, but operationally, the baton will be handed over."
"And that obviously came as a shock to myself, but what I've had time to do is to reflect over the last 12 hours or so. And I wanted to stand in front of all of you to break this news and just express my gratitude to each and every single member of the team that has given so much during the last 20 and a half years that I've been here," he further added. (Via Motorsport.com)
Christian Horner joined Red Bull back in 2005, at the time of its inception, and helped the team grab six Constructors' Championships and eight Drivers' titles. After Horner's dismissal, Red Bull appointed former Racing Bulls boss, Laurent Mekies, as its team principal with immediate effect.