It emerged earlier this month that Newcastle's Saudi owners are also major investors in Chelsea's new majority shareholder, Clearlake Capital.
And co-owners Amanda Staveley and Mehrdad Ghodoussi did little to play down the special relationship between the groups, attending Chelsea vs Tottenham at Stamford Bridge in Behdad Eghbali's executive box on Sunday.
Staveley, Ghodoussi and Eghbali, who led the £4.25billion Chelsea takeover as the face of the buy-out alongside Todd Boehly, were seen chatting in the upper tier of Stamford Bridge's West Stand before and during the game.
Eghbali is the co-founder of Clearlake, who bought 60 per cent of Chelsea in the takeover from Roman Abramovich this summer.