The Portuguese legend won 4 Ballon d'Ors, 4 Champion Leagues and a host of other trophies while he was a part of Los Blancos.
In lieu of this, here are the 5 most expensive transfers in the history of football.
Record breaking transfers in European football
Academy graduate returns home
Paul Pogba, a Manchester United Academy graduate, was sent to Juventus free of cost in 2012.
Little did United know, only after four years, they would be signing him back for a world-record fee of €105 million.
His biggest achievement with Juventus was winning 4 consecutive league titles.
This made United break the bank for the kid, Sir Alex had given away for free.
Dembele joins Barca as Neymar's replacement.
Dembele, the French forward, joined Barcelona for an initial fee of €105 million after Neymar left for PSG.
Notably, his deal also included add-ons worth millions.
Dembele signed a five-year contract with the Spanish giants with a buyout clause of €400 million.
Manager Valverde commented that his addition would bring in width to their attack, which they formerly lacked.
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When Coutinho finally joined his dream club
After a lot of speculation and drama surrounding his transfer, Philippe Coutinho finally joined Barcelona from Liverpool in January 2018 with a club record fee of €120 million.
The Liverpool number 10 was firing up the Premier League with his team-mates Salah, Firmino and Mane, when Barcelona came calling.
Even though Klopp was unhappy, the club finally let the Brazilian follow his dreams.
Mbappe quits Monaco to join PSG
After his wonderful 2016-17 season, in which he netted 26 goals in 44 matches for Monaco, the French international decided to join PSG on loan.
The subsequent full transfer fee which PSG would have to shell out, in 2018, is around €145 million, the second highest fee of all time.
But his form in the 2017-18 season proved the 19-year-old was worth every penny.
Neymar to PSG- The most expensive football transfer ever
The Brazilian superstar decided to quit Barcelona and move to the French capital after the 2016-17 season for €222 million, a transfer fee unheard of in the world.
Neymar had created a deadly triumvirate of attackers for Barcelona with Lionel Messi and Luis Suarez, which he replicated at Paris Saint-Germain with Cavani and Mbappe.
The transfer fee paid was his contractual release clause.
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