Sunderland's transfer deadline day business could be crucial as they look to bolster their squad for a promotion push in the second half of the season.

Ahead of tonight's 11pm deadline, the Black Cats are still working on a number of deals. Director of football Kristjaan Speakman and the club's recruitment team want to give manager Regis Le Bris the best possible squad as they challenge for an automatic promotion spot.

It has been an exciting window so far for Sunderland. A stunning move early in January saw them land Enzo Le Fee, initially on loan, from AS Roma. They haven't quite been able to make the big striker signing they wanted however, as moves for Ben Brereton Diaz and Tom Cannon were foiled when they joined rivals joined Sheffield United.

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A move for ex-Middlesbrough frontman Chuba Akpom and Sporting winger Marcus Edwards look doomed to failure, meaning that their stratgey of only bringing in the highest calibre of players may not pay off. However, with deals still being worked on, the hunt isn't over.

One thing Sunderland will be wary of too, however, is potential departures with a number of their talented youngsters attracting attention from the Premier League. here we take a look at the business that could be done before the deadline.

Pape Cherif Ndiaye from Red Star Belgrade

The Mirror are reporting that Sunderland could complete a late deal for Red Star Belgrade striker Pape Cherif Ndiaye ahead of the 11pm deadline.

The Senegalese international has scored 30 goals in 65 games for Belgrade including 13 in 16 league games this season - and twice in the Champions League. At 29 years old, he offers a wealth of experience and a good goal record. Sunderland are keen on adding proven goalscorer this month as their interest in Brereton Diaz and Cannon showed.

There is understood to be confidence on the player side that the move can be completed in time, Belgrade are reluctant to sell at this point in their season.

Tommy Watson to Brighton

Brighton are believed to still be keen on Tommy Watson despite having had a couple of offers rejected by Sunderland. The Premier League outfit have a long-standing interest in the winger.

It would be a blow for Regis Le Bris to lose the 18-year-old, given his lack of options on the left wing, unless a replacement could be sourced. "If Tommy did leave, we have to replace him,” Le Bris said. “We need two wingers on each flank, this is a better balance. Enzo can play here but only because we don't have others available at the moment.

Sky Sports reporter Keith Downie claimed that ‘the two clubs remain in dialogue’ despite Brighton having had a couple of bids rejected already. He claims that Brighton’s latest offer stands at £8.5million ‘plus significant add-ons’, with Watson only having 18 months left on his contract. That still doesn't meet Sunderland's £10m valuation of their breakout star but with Aston Villa and Crystal Palace also apparently monitoring Watson, it could make for a late deadline day dash.

Jayden Danns from Liverpool

Sunderland have been strongly linked with a move for Liverpool youngster Jayden Danns as they step up their hunt for a striker. The 19-year-old could leave Anfield on loan this month, with a number of clubs monitoring his status.

The Black Cats have chased striker reinforcements all window, missing out on Ben Brereton Diaz, Tom Cannon and others. However, they did secure the permanent signing of Wilson Isidor over the weekend, and with Eliezer Mayenda also in good form they could decide against adding another frontman to the squad and instead focus on the wide areas.

However, as they push for an automatic promotion place, Danns could add extra depth to the squad. The teenager is highly-rated and has a number of Championship clubs interested in signing him. Blackburn Rovers have made enquiries but reports suggest Hull City are now at the front of the queue.

Marcus Edwards from Sporting

Sunderland have been in talks with Portuguese outfit Sporting to sign Marcus Edwards. It would be a spectacular statement signing, with the former Tottenham Hotspur youngster having played top level European football before slipping down the pecking order. Reports suggest he may end up at Burnley, however, which would see the Black Cats lose out on another transfer target to a promotion rival.

Matthew Orr from Linfield

One for the future if this deal comes off. According to ESPN, Sunderland and Newcastle United are both keen on signing 17-year-old Linfield defender.

Newcastle have targeted the Irish market a lot recently, including the signing of youngster Kyle Fitzgerald from Galway, following the same path trodden by defender Alex Murphy. However, Sunderland are also experts in the Irish market, and signed Trai Hume from Linfield. Talking of Hume...

Trai Hume to Fulham

A bit of a left-field one with Premier League outfit Fulham reportedly interested in signing the Sunderland star. Fulham, who beat Newcastle at the weekend, have been keeping tabs on Hume who has had a good season on Wearside.

Right-back is an area Sunderland don't have much cover, however, and there appears to be no need to sell Hume at this pont ahead of a promotion push.