Here, Sky Sports takes an interactive look at how the competition between the two Manchester clubs has evolved throughout the Premier League era, with City slipping to the third tier before fighting back to overtake their neighbours.
Ivan Perisic, the Croatia worldwide, also featured prominently on Mourinho's wish list but it now seems that United's summer transfer business will be restricted to the arrivals of Fred, the injured Diogo Dalot and Lee Grant, signed from Stoke City as a third-choice goalkeeper.
Newcastle have again made a profit from player trading thanks to the sales of Mitrovic and Mikel Merino, with Benitez expressing his concern for the Magpies' prospects this season after a 4-0 friendly thrashing by Braga earlier this month.
The 2018/19 season gets under way with Manchester United taking on Leicester City at Old Trafford Friday. "I'm not confident and the market closes today so it is time, at least for me, to stop thinking about the market because the market will be closed, so I will have to focus on the players I have".
Mourinho sounded pessimistic that he would make any last-minute signings when talking to media on Thursday.
But this was only a "soft" closure - with some deals still able to be completed after this deadline.
Ander Herrera and Nemanja Matic are among six players ruled out of the game with injury, with captain Antonio Valencia, Marcos Rojo, Sergio Romero and Diogo Dalot also sidelined. "You can not expect them to be fit". I do think they have one over on City.
"My view is that first of all is hard for me to believe we finished second", he added.
Marcus Rashford, Victor Lindelof and Romelu Lukaku returned early and should be available.
Mourinho did confirm that Alexis Sanchez, who was a highlight for United over pre-season, is fit and firing though.
"Like any big club, they need some silverware - in his first season at Old Trafford, 2016-17, Mourinho won two trophies - the League Cup and Europa League - but he won nothing last season".