Manchester united playing Galatasaray at Galatasaray's home in their next champions league fixture is definitely going to be another though one for Manchester united as that fixture is a determinant for Galatasaray and they will be playing form home against Manchester united.
Galatasaray would not want to give a chance to Manchester united on this one because if they loose they are definitely going to be affected with their chances to qualify, they have four points with Copenhagen which is at the second position on the table, if they win and Copenhagen loose to Bayern Munich they are definitely sure of qualifying but if they draw then Copenhagen will have to loose for them to be sure of qualifying so the best alternative for them is to win which they are definitely going to make to that in their home, currently it looks like Manchester united with their current form needs a miracle to qualify.
The only hope for Manchester United is to win their match against Galatasaray, and if possible win Bayern Munich or draw them, but if they fail to win Galatasaray away from home, they need to put all their effort to win Bayern Munich which I know will be very hard for them unless they are lucky.
If Copenhangen can get a surprising win against Bayern, then it will be over for Both Galatasaray and Manchester Unite. But as it stand now, Galatasaray if they are able to win Manchester United will have hope of qualifying ahead of Copenhangen because winning Bayern will be hard for them.