Townsend, 24, has come up through the ranks at White Hart Lane, and has hit ten goals in 93 appearances for the club, even becoming an England regular off the back of his displays for Spurs.
However, Townsend's situation this season has been a difficult one. With just two starts in all competitions, Townsend has fallen well behind the likes of Christian Eriksen, Erik Lamela, Son Heung-min and Nacer Chadli, with manager Mauricio Pochettino seemingly not keen on the winger.
Matters appeared to come to a head back in November, when Townsend was seen arguing with fitness coach Nathan Gardiner, as reported by the Daily Mail, after a game with Aston Villa - a match which Townsend had to watch from the substitutes bench, as Pochettino preferred to bring teenager Joshua Onomah on instead.
Townsend hasn't featured since, and has even been sent down to play with the Tottenham Under-21's, all of which has pointed to a January exit for the wide man.
Many Premier League clubs are believed to be interested in his signature, but The Independent report that Sunderland have won the race, beating off competition from Newcastle, Watford and West Bromwich Albion, with Townsend allegedly set to make his move early into the January transfer window.
The Black Cats are mired in a relegation battle, and will need goals to keep them in the Premier League; and it's reported that manager Sam Allardyce believes Townsend is the man to provide a spark in the final third for his Sunderland side.
It's also stated that Townsend - who needs first team football to get into the England squad for next summer's European Championships - will earn a significant increase on his current £40,000-per-week contract at Tottenham, with Sunderland making a serious financial commitment in order to lure him to the Stadium of Light.
Would Townsend be a good signing for Sunderland?