Casemiro would likely leave Manchester United, but i don't think it can be to PSG. I found it weird when United paid £70m for a player of his age, there is no doubting his quality, but when a player is already above 30, he should not cost as much as that, except it is a Saudi club that is doing the signing, lol.
Buying a player from 28 and above is risky. Some of them will experience a drop in performance, others will become injury-prone and their injuries will take more time to heal. Paying Real Madrid such an amount for an aging midfielder might be an error but they thought he would deliver, but sadly he underperformed. But there is still interest for the Brazilian which shows that he is still relevant to some clubs. But there are speculations that the Brazilian has an interest in moving to Bayern Munich. With the future of Thomas Tuchel in doubt and rumors that Xavi Alonso might be moving to Allianz Arena, Casemiro might want to reunite with his former teammate.Quote
PSG are looking for younger players, especially from France, that is the direction the club has decided to take, they no longer want to sign only big stars, but they want to nurture young talents, if Casemiro leaves United, Saudi Arabia would be a more likely destination that the French champions.
A report claimed that Real Madrid dropped the bid of signing Mbappé because of his age. And a close look at Real's new signings shows that they are interested in young player. PSG should raise or sign young players and allow advanced players to move to Saudi Arabia 
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