Colgan, who was released by Ipswich this summer, is a surprise acquisition as Keane already has Craig Gordon, Darren Ward and Marton Fulop on his books.

But the 34-year-old has signed a one-year deal with Sunderland, who become Colgan's 13th league club in England and Scotland following a move to Chelsea from Drogheda United in 1991.

"It's a huge challenge I'm really looking forward to," said Colgan on the club's official website.

"I got the call from the gaffer and he gave me 24 hours to think about it, but I think it took me about 24 seconds to decide!

"He told me he wants to carry a good squad of goalkeepers and it's my job to bring my experience to the other keepers and to add some pressure on them and keep them on their toes."