SUNDERLAND have cushioned the blow of having to pay out up to £1m on three of their summer signings by adding Birmingham City's Darren Carter to their ranks.

Carter's arrival, on a three- month loan, has moved Sean Thornton a step closer to leaving the Stadium of Light.

Thornton, courted by Everton in January, has handed in a transfer request after struggling to force his way into Mick McCarthy's first team plans.

McCarthy has acted quickly to bolster his ranks by getting Carter.

Thornton, who may be loaned out until the transfer window opens in January, is well down the pecking order. Jeff Whitley, Carl Robinson, Dean Whitehead and now Carter are ahead of him in the battle for a central midfield role.

Carter made eight appearances for Steve Bruce's side last season and he made a name for himself in the 2002 play-off final, when he scored the penalty that secured the Blues' place back in the top-flight.

McCarthy has been keeping an eye on the 20-year-old and the Sunderland boss said: "I'm absolutely delighted to secure the signing of Darren.

"He's a central midfielder and a left-footer with great presence. I've watched and admired him for a long time so it's great to be able to bring him to the club - he'll be a good addition."

Carter's capture came on the day it was announced that a Football League tribunal has ruled the Wearsiders could end up paying more than £1m for Stephen Elliott, Liam Lawrence and Whitehead.

All three were out of contract in the close-season and Sunderland pounced to acquire the trio's services.

But, as they were all under 24, the Black Cats have to pay compensation fees to their first clubs - initially amounting to just £450,000 for all three.

Despite that figure possibly rising to a seven-figure sum, Sunderland chairman Bob Murray insisted he is happy with the outcome of the tribunal in Manchester.

Murray said: "Mick identified all three players as exciting young prospects and we were determined to bring them to Sunderland. I'm confident all three will prove to be good signings so we fully expected to pay out a reasonable level of compensation."

Sunderland have to pay £125,000 up front to Manchester City for striker Elliott, with an extra £20,000 being paid for every ten appearances he makes up to 50.

Whitehead has come from Oxford United at a cost of £175,000, which goes up by £15,000 every time he reaches ten games up to 50 matches. Lawrence, who left Mansfield, will initially cost the same as Whitehead, but could rise to £375,000.

Sunderland will also have to pay £100,000 on each deal if they win promotion to the Premiership and a further £50,000 for each player if they become senior internationals. There is also a 25 per cent sell-on clause.

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