If his bruising is bad enough to keep him out of international duty that is a shame. I don't think we will lose to Fulham with or without him, 1-1 is my prediction without seeing the teams.
One positive about the assumed Gaston injury is that it sounds like it was a bruise from a heavy hit rather than a strain. Although you can't tell how injury prone someone is without some serious analysis it would appear that he hasn't picked up a hamstring, groin, or calf tear that injury prone players seem to always pick up.