The Sunderland defender is currently on loan at Sporting Lisbon.
The defender departed the Stadium of Light last January, joining the Portuguese giants until the end of the season.
That move was extended in the summer when he joined on a season-long loan deal.
Sporting's Coates challenges Cristiano Ronaldo
He has since established himself at the Estadio Jose Alvalade, playing in all of their league games this season, as well as their four in the Champions League.
His move included an agreement for the switch to be made permanent at the end of this season for £4.3 million, according to the Chronicle.
Uruguay defender Sebastian Coates
However, a reported major stumbling block was that Jorge Jesus’ side may not be able to afford his wages.
According to Record, that problem could be about to be fixed as the 26-year-old is willing to take a pay cut to secure himself a five-year deal in Portugal.
That will come as good news for the Black Cats, who would stand to make a £2 million profit on a player who is surplus to requirements in the North East.
Sporting Lisbon's Sebastian Coates