Sunderland's penny pinching summer has accumulated to a net spend of around - £70 million, having lost several key players and spending in the region of just £1.5 million in the process. 

Whabi Khazri is set to join Jordan Pickford and Jermaine Lens on the club's departures list, but Simon Grayson and Sunderland fans alike should perhaps be more concerned about the rumours regarding Didier N'Dong moving on before tonight's deadline.

N'Dong, who has played in every competitive game for the Black Cats this season, is reportedly subject to interest from Lyon and West Ham.

The latter's pursuit may depend on the capture of William Carvalho from Sporting Lisbon, who in a bizzare twist could court Sunderland's Jack Rodwell as Carvalho's replacement.

However, not to be unkind to Rodwell, Sunderland would much sooner keep hold the Gabon international, unless Chairman Ellis Short sees further asset stripping to be necessary, this time in the form of their record signing.

N'Dong has played in a 4-4-2 alongside Lee Cattermole and Darron Gibson in the league and cup respectively, with his high-energy game enabling his less mobile counterparts to concentrate on their utilise their best aspects .

The favoured formation has unraveled somewhat in recent weeks as Sunderland fell to two consecutive league defeats, including a humbling 3-0 reverse away at Barnsley, in which they looked tired and ragged.

But if Grayson is to persevere with it, he must keep N'Dong who is the engine room in his midfield and with the limited options at his disposal, the boss will be left with a depleted midfield, regardless of whether he alters the system or not.

N'Dong was one of the shining lights in a much maligned Sunderland side last year, with many tipping the 23-year-old to be one of the pillars of the new era on Wearside.

Selling the ex-Lorient man today would hamper Sunderland's progress greatly.