Manchester City and Manchester United have been told Newcastle United 'will make mistakes' and 'take time to adjust' upon winning the jackpot.

In a seismic £305million deal, the Magpies have new owners after a consortium backed by the Saudi Arabia Public Investment Fund (PIF) struck up an agreement with now-former chairman Mike Ashley.

As a result, they are set to become major players in the global transfer market moving forward.

However, that won't necessarily come as an instant threat to City and United — or other top-flight contenders.

That's the message from former Chelsea and West Ham player Joe Cole, who switched across London to Stamford Bridge shortly after Russian billionaire Roman Abramovich purchased the Blues in time for the 2003/2004 campaign.

Cole was one of several high-profile signings after that takeover, while Chelsea won their first Premier League two seasons later under Jose Mourinho.

Speaking as part of a promotion for bookmakers Coral, the former England playmaker said: "When Chelsea did it, they were only really competing with Arsenal and Manchester United to get to the top, for players. Newcastle are in the market now, for instance, for [Mauro] Icardi from Paris Saint-Germain, a top striker, who maybe is available.

"They're also competing with four or five other teams in this league who probably like the look of Icardi.

"The landscape's different, but the people from Newcastle would be wise to really lean on someone with wisdom, who has overseen these things or even someone who's been involved in the eye of the storm, you know, who can say; 'This is what can happen. These are the problems you'll face'."

Cole added: "From a footballing aspect, you know, these guys are business people. They know what they're doing. But football is and will always be acquired and the amount of knowledge, that you can only get really by playing in it and being on the inside, the inner echelons of it, because it's so unique as a sport.

"So they will do wise to get people around them who they can trust, who have done that.

"They'll make mistakes. They'll sign players that don't work, like every club, and they'll probably lose a lot of money, but it's going to be exciting. And what a rollercoaster."

The new owners' era at Newcastle began with a 3-2 home defeat by Tottenham.

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