Paris Saint-Germain have signed Ander Herrera from Manchester United on a free transfer, the club announced Thursday.

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Herrera's five-year stay at United came to an end after he failed to agree a contract extension with the club.

He will wear the No. 21 with his new club.

"Paris Saint-Germain is the greatest club in France," Herrera said. "It keeps on improving and competes to win every possible title. I was looking forward to coming to Paris and to wearing those colours. I hope to continue to make history with the club!

"Joining this club is an amazing feeling. I also love the city. Paris is the most beautiful city in the world. I promise three things: work, professionalism and passion. I also promise to improve my French because I think that the language is very important for the team's communication."

Sources told ESPN FC last week that PSG waited for the new financial year to begin before announcing the Spaniard's arrival.

Herrera will replace Adrien Rabiot in the PSG midfield with the France international set to depart on a free transfer.

Herrera's debut is likely to be the Trophee des Champions against Rennes -- who beat PSG in the French Cup -- on Aug. 3.

Herrera joined United from Athletic Bilbao in 2015 and won the FA Cup, League Cup and Europa League.