Celtic have warned potential suitors that Polish goalkeeper Artur Boruc is not for sale.
The colourful goalkeeper's future has been the subject of speculation following the signing of fellow Pole Lukasz Zaluska.
A number of clubs are thought to be monitoring Boruc's situation in Glasgow, but Celtic chief executive Peter Lawwell insists the club plan to keep Boruc.
"Artur Boruc is not for sale," said Lawwell.
"He's the best goalkeeper in Europe and, despite speculation to the contrary, we are holding on to him.
"There have been no offers for him and we don't want any.
"Tony [Mowbray] has had a close look at him and has been really impressed. He is perfectly happy to have him as our number one for the new season."
However, Mowbray is willing to let third-choice keeper Mark Brown leave the club.
"We have a lot of keepers now and if the right chance comes along for Mark Brown then I would not stand in his way but Artur is staying," Mowbray told the Scottish Sunday Express: