The 22-year-old will make a decision on his future at the end of the season and he has hinted recently that he would like to stay at the Wearside club.
"A permanent move is impossible because we have great expectations for the player," Villas-Boas said earlier in the season.
"He has a bright future. We appreciate what he's been doing there and it's been a great experience.
"He's been extremely well managed. We can't give away a player of his quality."