PSG wanted to balance the books with UEFA sniffing around a potential FFP breach
The Catalans made an offer which was below the player's value
According to Radio Montecarlo (RMC), Angel Di Maria's transfer to Barcelona fell through on deadline day because of UEFA opening an investigation into PSG for a possible infraction of Financial Fair Play and Barcelona trying to take advantage of this situation.
Once they were unable to sign Philippe Coutinho, Barcelona decided to move for Di Maria during the final day of the window, September 1.
With UEFA investigating PSG after Neymar's move, Barcelona wanted to capitalise. They wanted to use their position of strength. PSG needed to sell a player to balance the books, needing 80 million euros for that. The Blaugrana tried to sign him for less than PSG's demands.
