Off the back of a groin problem I would not risk Given. He'll not be 100%. No chance. Guzan should play.
Given has always taken a long time to get over muscle strains and now at his age it will take longer still. It's too big a risk to pick him.
Absolutely hope Guzan plays. Others have made these points already but I don't trust Given rushing back from injury after the Euro's and this is a fairytale story for Guzan if it comes through. Balance in the universe will be restored after 2010.