Manquillo spent the 2016-17 campaign on loan at Sunderland from Spanish giants Atletico Madrid.
Sunderland struggled last season and dropped down to the Championship, with Manquillo subsequently joining their bitter rivals Newcastle on a permanent contract from Atletico in the summer transfer window.
According to The Chronicle, Newcastle had to pay Atletico a transfer fee of £4.5 million in order to secure the services of the former Spain Under-21 international right-back.
Sunderland would have had to to pay Atletico £9.5m if Manquillo played 25 matches for them last season, according to a report in The Chronicle in November 2016.
Manquillo has admitted that he does not know why he did not play more than 20 times for Sunderland - who were then managed by David Moyes - last season, and has also spoken about his time spent at the Stadium of Light.
When asked about the politics of his transfer situation at Sunderland, Manquillo told The Chronicle: “You would have to ask David Moyes about that. I don’t know why.”
“I never had any problems with him,” added the defender about his relationship with Moyes. “I just had a hard season but I have never had conflict or personal issues with him.”
Manquillo said about his time at the Stadium of Light: “Sunderland was really tough but like everything in life, you learn from things that have gone wrong. In a way, that difficult year made me a better player.”