Sunderland have signed Manchester United forward Amad Diallo on a season-long loan and France youth midfielders Edouard Michut and Abdoullah Ba.
Ivorian Diallo, 20, joined United from Atalanta for £19m in January 2021 but has only played nine senior games.
He spent the second half of last season on loan with Rangers.
Michut, 19, joins the Black Cats on a season's loan from Paris St-Germain with an option to buy, while Ba, also 19, has signed a five-year deal.
He has moved permanently from Le Havre.
It is understood Diallo's wages are being split between Sunderland and United.
"I had a fantastic experience at Paris St-Germain, but now I'm ready for a new challenge," said Michut.
"I travelled to the Stadium of Light on Saturday to watch the game against Norwich City and the atmosphere inside the stadium was unbelievable.
"This is an opportunity for me to level up as a player and I always wanted to play in England, but I also like the project and that is why I'm here. My preparation for the season has been good and I'm ready to help the team."
Ba said: "I'm very happy to be here because this is a big club and one that has a lot of ambition.
"I want to make a lot of progress and make sure we keep building on our history."
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