"He is the one in our dressing room that can truly say he has played at the highest level - in World Cups, in Europe, in cup finals and so on.

"We have to negotiate and see where we go, but players have to want to stay here and we have to want to keep them.

"Mark has been here a long time so he has to decide if he needs a fresh challenge, whether what we are trying to do is going to excite him, whether he feels he is going to be appreciated here."

Boro, who have confirmed that Fabio Rochemback, Gaizka Mendieta and Dong Gook Lee will all be leaving Teesside this summer, have also confirmed they have offered striker Tom Craddock and right-back Tony McMahon one-year extensions to their current deals, which run out this summer.