The Black Cats are reportedly weighing up a move for the enigmatic Belgian.
The 28-year old has failed to command a first-team berth under Mauricio Pochettino - starting just 10 Premier League games last season - and Dick Advocaat is reportedly keen on reuniting with the player he managed at AZ Alkmaar.
Up for sale?
Despite his tremendous ball-carrying ability and all-round technique, Dembele has often been a source of frustration for Spurs fans due to his knack for routinely underwhelming.
There is the sense that he could offer so much more and consistently hurt the opposition, yet too often fails to truly make his mark on games.
That being said, the composure and ball-retention he brings to the Spurs side can be invaluable, particularly when brought off the bench late in games and he has an underrated ability to retrieve possession, as well as keep it.
Dembele is the only remaining central midfielder with more than 18 months of Premier League experience, and at 28 is one of the youthful squad’s senior figures.
Whilst not entirely suited to Pochettino's pressing system, the Belgian remains a tremendous talent and one of the most naturally gifted players in the Premier League.
The Argentine utilised him just enough last season to suggest he values his contribution and Spurs fans will be hoping next season brings out the Mousa Dembele we've seen in glimpses on a much more consistent basis.