Sir Jim Ratcliffe says he needs to embark on a culture transformation at Manchester United because the club is not geared for success. The British billionaire’s 27.7% minority shareholding purchase was completed on Tuesday and he has set about making key appointments as part of a restructure.

Omar Berrada will join as chief executive in the summer from Manchester City and talks continue to bring the Newcastle sporting director, Dan Ashworth, and Southampton’s director of football, Jason Wilcox, into senior roles. A deputy chief executive is also wanted as Ratcliffe aims to make “world-class” appointments to help facilitate change on the pitch.

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“We have to look at the organisation of the club, because it is not good at the moment,” Ratcliffe told the Belgian newspaper De Tijd. “Take the head coach [Erik ten Hag] for example: he must report directly to the CEO. That is no longer possible in a modern football organisation.

“We then have to ensure that the right people end up in the right positions. Every person in management must be world-class. And then it is important to create a positive, supportive, friendly and high-quality environment. That culture was missing before. Only in such an environment can you get the best out of sportsmen. If successful, the results will follow automatically. That’s the plan and I believe in it.”

Ratcliffe has played an active role forming the new structure, alongside the Ineos director of sport, Sir Dave Brailsford, and chief executive of sport, Jean-Claude Blanc, who will take positions on United’s board. Berrada wants to form a tight management team at the top of the club to help bring it into the new era.

United are sixth in the Premier League, five points behind fourth place as they look to reach the Champions League, having failed to progress past the group stages this season. The club have lifted one major trophy in the past six seasons and have not won the Premier League since 2013.