The Black Cats are currently negotiating a deal with Atletico Madrid, according to 'Sky Sports'.
Manquillo joined Liverpool on a two-year loan deal from Atletico two years ago, but the Reds cut the player's loan short after just one season and 10 Premier League appearances.
The 22-year-old enjoyed a more successfull spell at Ligue 1 side Marseille last season, where he played 43 times.
Despite this, the player has no future at Atletico Madrid and David Moyes is hoping to bring the former Spain U-21 international to Wearside.