The key transfer business Sunderland must pull off this summer if Black Cats are to win promotion

The Black Cats are looking to add the key players to a squad they hope will win promotion back to the Championship.

The club fell short last season, missing out on automatic promotion in the final weeks of the season before that cruellest of defeats at Wembley at the end of May.

Work to strengthen the squad is ongoing, and former Sunderland players Gary Bennett and Kieron Brady have outlined the key areas that need to be strengthened.

The centre of defence is one priority, and adding goals up the other end of the pitch another - with calls for a 20-goal-a-season striker to be signed.

Sunderland used five different centre-backs last season, with Tom Flanagan, Jack Baldwin, Alim Ozturk, Glenn Loovens and Jimmy Dunne all fielded at different stages.

Flanagan and Baldwin played much of the season together but the former Peterborough United skipper spent the end of the season watching from the sidelines following a series of mistakes.

Ozturk came into the team alongside Flanagan and impressed, though it remains to be seen whether Jack Ross sees him as a first-choice starter next season.

Dunne has already returned to Burnley following his loan spell, while Loovens has another year on his contract but may still depart the Stadium of Light this summer.

Former skipper Bennett, who made more than 350 appearances for the club, said: “Central defence would be a key area, everybody knows where we need to strengthen and that includes centre-backs.

“You have to get the centre of defence right, have that presence in there, players who can command the area, head it, have a bit of pace and have knowledge of this level.

“In midfield, you need someone enthusiastic and bright on the ball, and creative. Someone who can open doors and create chances but also score goals too.

“Striker-wise, we need someone who will score 20 goals a season to get us out of this league.”

Sunderland splashed the cash on Will Grigg in January, a £3million fee securing his services from Wigan Athletic.

But his form suffered as a result of a niggling ankle problem, the Northern Ireland international scoring just five goals in the second half of the season.

Bennett has sympathy with the striker, with Grigg used in a couple of different formations, but says ultimately Sunderland won’t get the best out of him until he is fully fit.

A summer of rest will hopefully help provide the spark needed to get Grigg firing next season.

On Grigg, Bennett added: “You have to look at did we create enough chances for him? Did he get much time on the pitch? Which was his best position?

“Was he best playing with a Chris Maguire or a Charlie Wyke?

“Or that midfield player that can link up with him? He knows he needs to be fit first of all and then go from there.”

Ex-Sunderland winger Brady hopes Ross is given the funds needed to add the players in key areas to mount a push at winning the title - though he admits the pressure will be on Ross given the failure to land promotion last season.

Brady said: “The manager should be given funds now to try to build a squad that won’t only compete in League One but also strive towards being champions, and comfortably so.

“As even then, if you fall short to a certain extent, then it should still be enough to win automatic promotion.

“What I think Jack is confronted with now is that he will effectively start the new season on trial, certainly in a manner that he wasn’t in the season just gone.”

In terms of the summer transfer business, Brady was clear which areas were key for Sunderland to focus their business on.

Brady agrees with Bennett that another striker is a priority, while the former midfielder also wants to see a new right-back signed.

Sunderland deployed midfielder Luke O’Nien at full-back for much of last season but with Adam Matthews departing on a free, reinforcements are needed.

Brady said: “I think they need a centre forward. They could do with someone who could come in and play at right-back.

“That is in no way to be dismissive of Luke O’Nien, I have the greatest admiration for him the way he performed last season, his work ethic.

“It will depend on the money available to Jack Ross. In an ideal world, I think he would want to bring in a better standard of player in almost every position.

“But that may not be realistic. I think certainly a right-back, a centre forward and someone who will be creative behind them, the old style No.10.

“Of course, all this will depend on the resources the manager has at his disposal.”

Sunderland are set for a fresh injection of investment this week, with the Mark Campbell-led takeover expected to go through in the newxt few days.