Sunderland are going to have plenty of business to do as the summer transfer window looms.

A large number of first team players are out of contract at the end of the season which means that the recruitment team may have their work cut out as they look to secure replacements, and maybe even upgrades.

A key factor in the business that's done is likely to be which league the club finds themselves in, with promotion to the Championship likely to open the door to a higher caliber of player.

However if they're in League One there will still be improvements to make in order to target promotion next term.

Sunderland have been linked with plenty of players so far this term, with January being big as the club looked towards mid-season additions.

With that in mind here are seven rumours from January that Sunderland may revisit in the coming months.

The search for a left-back could be a big priority this summer.

Sunderland were linked with a move for Josh Doig during the January transfer window as Lee Johnson looked to add competition for places alongside Callum McFadzean and Denver Hume.

The 18-year-old enjoyed an excellent breakthrough season with Hibernian and as a result may well attract significant interest this summer.

Whether Sunderland will look to renew their efforts to sign him remains to be seen, but given that he's only going to improve it could prove to be a very shrewd addition indeed.

The striker is bound to be a big talking point this summer.

Will Grigg was heavily linked with a number of clubs in League One, including Shrewsbury Town before eventually completing a short-term switch to MK Dons.

Since then the striker has certainly re-lit his fire.

Grigg has scored eight times in the second half of the season and with another year remaining on his contract it means that interest is likely to be high in his services this summer.

Depending on how Sunderland's recruitment drive goes, there's even the outside chance that he could be afforded another chance at the Stadium Of Light.

A long-term target for Sunderland.

Kevin Nisbet emerged as a target for the Black Cats back in January, however no move happened at the mid-point in the season.

The 24-year-old has enjoyed a wonderful season with Hibernian after scoring 17 and creating eight for the Scottish side, leading to reported interest from Brentford.

Sunderland are almost certain to be looking for a striker this summer and if given the chance then Nisbet could prove himself to be an ideal addition for Lee Johnson's side ahead of the new season.

The striker is bound to be at the top of several club's shopping lists in the summer.

Football League World exclusively revealed that Sunderland and Charlton Athletic were keen on a move for Jayden Stockley during the January window, with the Preston North End man opting to move to the Valley.

Since then the 27-year-old has scored eight goals for the Addicks and played a big role in their pursuit of a play-off spot.

With his future at Deepdale likely to be in doubt it seems that Stockley could be on the move, and given his powerful stature in attack he may well be seen as the ideal man to potentially replace Charlie Wyke in attack.

Stockley would be a really shrewd addition for Sunderland and one who would easily fit into Lee Johnson's plans.

Paul Osew is another player who was linked with a move to Sunderland in the January transfer window.

The full-back has enjoyed an promising season with AFC Wimbledon after making 13 appearances for the League One club this term, establishing himself as one of the hottest prospects in League One.

While regular starts have been hard to come by there's no doubting that the 20-year-old is tipped for a big career in the EFL and that's something that could appeal to Sunderland.

Osew is a left-back and with Lee Johnson likely to be looking at options to improve that area then such a cost-effective deal could prove to be very appealing.

Whether he's ready to be a first team regular, however, remains to be seen.

Left-back is bound to be a big focus, and that's why the position was so heavily targeted during the January transfer window.

Football Insider linked Sunderland with a move for Scott Tanser at the start of the year and it's likely that their interest will only have built over the last few months of the season.

The 26-year-old has been a key performer for St Johnstone in the Scottish Premiership, but has struggled with an ankle injury of late which has disrupted his season.

Tanser is out of contract this summer which means that he'd certainly offer a bargain solution to the club's problem, and given the level of his performances there seems to be no doubt that he'd be a player who could make an immediate impact under Lee Johnson.

A player who was heavily linked with Sunderland in the January transfer window before making his loan move to the Stadium Of Light.

Jordan Jones has showed glimpses of real quality during his time under Lee Johnson, scoring three goals and creating four more for the Black Cats in that time.

Rangers are reportedly happy to see the player leave the club - something that could really play into Sunderland's hands.

Football Insider have claimed that the 26-year-old would be happy to return to Wearside next term, and if that is the case, it could prove to be the signing of the summer for the Black Cats.