If we sold Guzan we'd have to spend at least as much on a replacement second choice keeper. Marshall is just about acceptable as a third choice keeper, and I don't think we have a young keeper ready to step up yet.So unless it's for £4 million + and we can get someone as good for less, then it's a false economy to sell him.
I'm not sure the thread starter realises Guzan is actually out of contract in June! He can start talking to foreign clubs in Jauary and agree a free deal in the summer.I'd offer him a new contract without hesitation tbh, he's shown he can challenge Given properly.
Given has been quite injury prone the last few seasons so I'd give Brad a new contract too.