Arsenal first match in this competition and they will fight against PSV and this is very interesting because both teams have been met last year on Europa league and both teams have defeated each other which mean PSV can be considers as tough opponent for Arsenal especially PSV performance were increase rapidly because since July PSV has fantastic achievement and since that month PSV has through 11 matches with unbeatable status in all competitions and before they advances to the group stage PSV has been done a good job because they can able to eliminate Rangers with total aggregate 7-2 so although Arsenal is the favourite in this match but PSV cannot be underestimate because they have a potention to make Arsenal get in trouble
I think this game should end in favor of Arsenal although I know that PSV isn't easy to play against, but still the difference in quality is too much if everything goes as expected for Arsenal. It is also a home game for them, which makes it even less likely for PSV to come up with a surprise game. But there is still some time left until those games take place, but Arsenal should be off for a good start into the Champions League season.