The 21-year-old has less than 12 months remaining on his current deal at the Stadium of Light and had been a transfer target for newly promoted Leicester City.
However it is now being reported that Ronald Koeman considers the young striker to be an ideal replacement for Rickie Lambert at Southampton, and is weighing up a move to bring the England under-21 international to St Mary's.
Wickham demonstrated his Premier League potential last term scoring five goals in the final 12 games of the season for Sunderland and almost single handedly clawed the Black Cats out of the relegation zone.
Sunderland had been nailed on to go down after being bottom of the table at Christmas, but the return of Wickham from a loan spell in the Championship added some much needed fire-power to Poyet's side, who eventually pulled off a remarkable survival with the 21-year-old spearheading the Sunderland attack.
After finally making an impact in England's top flight, the striker has a real chance of being a staple part of Poyet's first XI next season.
Sunderland are reported to have rejected an approach from Leicester earlier this week, which would indicate that the Uruguayan manager very much visions Wickham in his immediate plans for the upcoming campaign.
Sunderland paid in excess of £8million for Wickham in 2011 and are thought to be in talks with their young forward regarding a contract extension to ensure their investment isn't wasted, with the youngster leaving on a free transfer.
But the fact that club and player are in contract talks does not necessarily indicate Wickham's future lies at Sunderland, nor does it rule Southampton or Leicester out of the race.
With his contract running down and with obvious interest from elsewhere, the 21-year-old now has some leverage with which to negotiate himself a deal that suits him best.
Wickham has proven that he is ready to be a first choice Premier League centre-forward and will no doubt demand such a role in any potential new deal at Sunderland. If the Black Cats cannot promise this, then Southampton might be a very real destination for the striker.