"The only slight cause for concern is on the margin front, " he added.

BBC: John Lewis sees 'outstanding' Christmas sales

Greater challenges will lie ahead for Arsene Wenger's side - but the victory margin was a fair reflection on their superiority in front of an elated Emirates gallery.

BBC: Arsenal 5-0 Porto (6-2)

Greece produced only two genuine attempts on goal while, in contrast, Huh Jung-moo's team should have won by a larger margin had Monaco striker Park Chu-young been more clinical in front of goal.

BBC: South Korea 2-0 Greece