Arsenal will not be rash when hosting PSG tonight they will be quite careful in this first leg match because they are important to win especially in a large number of goals.
I think in the first leg if the result is a draw then the possibility of Arsenal will be difficult in the second leg at home to PSG, so as much as possible Arsenal must win tonight at least it would be better.
Again Arsenal is Arsenal and they lost at their home stadium, and even result is only 0 - 1, it's disappointed result for them. Arsenal actually faced with a bigger defeat but they were lucky because PSG players wasted some opportunities to expand it to like 0 - 2 or 0 - 3. Perhaps this minimal defeat will make a second leg more exciting and Arsenal will feel they still have chance in Paris.
With PSG, hopefully they won't pay expensive cost by opportunites wasted in this first leg, but again PSG for another time move closely to UEFA Champions League final match.