MICK McCarthy is expecting a summer of protracted transfer wrangling after admitting that Sunderland do not have a "divine right" to cherry pick the best players in Division One.

The Black Cats boss began his close season clear-out on Friday by releasing Jason McAteer, Phil Babb, Joachim Bjorklund and Paul Thirlwell.

Youngsters Michael Reddy, Mark Rossiter, Simon Ramsden and Patrick Collins were also shown the door and, while talks continue with six other out of contract players, McCarthy has already turned his attention to the transfer market.

A host of players have become free agents this summer and, after trimming their wage bill since last week's play-off defeat to Crystal Palace, Sunderland are in a position to strengthen their ranks.

The club's history and the infrastructure at the Stadium of Light, make the Black Cats an attractive proposition to most players outside the Premiership.

But McCarthy has dismissed suggestions that Sunderland will start at an advantage over their First Division rivals in the race to attract new blood.

"It's all very well saying there are loads of players out there, but they will have choices as well," said the former Republic of Ireland manager. "It's not like we have the divine right to pick up what players we want.

"We saw that earlier this year with Andy Gray and Simon Francis. We wanted them here, but they chose to go to Sheffield United and were free to go there.

"They had a choice. We are still a First Division club and we have to recognise that there are constraints. There are constraints in the Premier League now and we have to address that.

"There doesn't seem to be as much doom and gloom as there was last year. Last year everything was about finances and losing big salaries, but I will still have to do things sensibly."

The Black Cats will be forced to look on enviously as Crystal Palace take on West Ham for a place in the Premiership on Saturday.

The First Division play-off final is of little interest on Wearside now, but last year's end of season shoot-out offers a stark warning to the Black Cats.

Reading and Nottingham Forest were the beaten semi-finalists on that occasion, with Sheffield United missing out in Cardiff, and none of the three have featured this time around.

Reading and Sheffield United were in the running for most of the season, but Forest only narrowly avoided dropping into Division Two, and McCarthy is desperate to prevent things going stale after last week's disappointment.

"I think about Nottingham Forest and Sheffield United getting to the play-offs last year and it does need freshening up," he said.

"There's no question about that and it's important that we don't become stale or stand still. After this season, I think a lot of the players need a fresh challenge.

"It will be interesting to see who is out there. There will be swaps and trades and everybody will be wanting to freshen things up."

McCarthy's immediate priority remains the six out of contract players he offered new deals to last week.

Jeff Whitley, Darren Byfield, Tommy Smith, Richie Ryan and Neil Teggart are currently considering what was put on the table, and all are expected to respond this week.

But winger John Oster could opt to keep his cards closer to his chest after West Ham revealed their interest in taking him to Upton Park.

The Hammers have been impressed with Oster's lively showings this season and, should they make it to the top-flight this weekend, the Wales international is expected to move south.

A West Ham defeat could complicate the situation, but Oster is unlikely to commit himself to anything until the fate of Alan Pardew's side is known.

The future of Newcastle centre-half Stephen Caldwell is more certain, with the Scotland international expected to sign for Sunderland when his current St James' Park deal expires next month.

Caldwell spent the second half of last season on loan at Leeds United and has been told he is surplus to requirements on Tyneside.

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