Kevin Phillips says is is 'critical' that Sunderland keep top scorer Ross Stewart on Wearside after his goals powered the club to promotion. Scotland international Stewart scored 24 league goals, and two more in the play-offs, as the Black Cats clambered out of League One and back into the Championship.

But the 25-year-old's form has inevitably attracted interest from elsewhere, with Scottish Premiership side Glasgow Rangers rumoured to be keeping tabs on the former Ross County hitman. Stewart is about to enter the final 12 months of his contract at Sunderland and the club has already said that it is seeking to hold talks with him over a new long-term deal.

And Sunderland legend Phillips, the club's record post-war goalscorer, says holding onto Stewart is a priority, alongside backing head coach Alex Neil in the transfer market this summer. "The big thing now is what financial support is going to be given to Alex," said Phillips, who now manages South Shields.

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"Can they nail down players like Ross Stewart? He has only got a year left and it is critical that they keep him.

"Alex is certainly the right man for the job to move the club forward, but he needs the backing and the finances. I don't think they need an awful lot, but obviously they will need some new players."

Sunderland will return to the Championship next season after a four-year absence, and Phillips says they must gain a foothold in the second tier next term - and avoid at all costs the kind of instant return to League One that other promoted sides such as Charlton, Wycombe, Rotherham, and Peterborough, have faced in recent seasons. Phillips said: "They have to make sure they never find themselves there again.

"Lessons need to be learned, and I think they will be. Just because you are a big club with a big fanbase, it doesn't guarantee you anything unless you do things right on and off the pitch.

"Now Sunderland have got out of League One, they mustn't get too far ahead of themselves next year - it's about making sure they stay in the Championship, I think they will do that comfortably with a few additions, and then they need to build from there. First things first, though, they deserve massive credit for getting back into the Championship."

Phillips is a big admirer of the job that Neil has done since he succeeded Lee Johnson in February, and admits he would be happy to take on board any advice that the Scot can offer. He said: "He's made a massive difference.

"I said to him after the [play-off final] that I'd like to pick his brains for a couple of hours to see what he has done differently. You could see that Sunderland were a lot more defensively solid since he went in there, he found a style and a system that suited the players, and the players stepped up to the plate.

"It looked like the players were playing with smiles on their faces, they were enjoying their football, and it got results."

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