There is no doubt that Arsenal is among the favourites in the Europa League. They are lucky because Manchester United will face Barcelona, which means either of them will be eliminated and give the more possibility that Arsenal can progress to the top level of the Europa League.
But Arteta should be very careful and decisive because he might lose all if he decides to chase both Epl and Europa.
The problem arsenal now is difficult to win if faces a strong club. Like last night, Arsenal lost in the home after face Man City, we don't know what happen, maybe Pep is a teacher and Arteta don't know how to beat him when face to face. And next when meet a strong club from spain like Barcelona you said, maybe Arteta and team will get the hard presure and difficult to win.
Arsenal's defeat in last night's match was purely the fault of the Gunners players. in particular, Timiyasu. The smell of defeat has been seen, since the beginning of the first half started. I'm not sure why Timiyasu underperformed last night. because he doesn't normally play so badly. apart from that, Zinchenko also did not play in his usual form. fatally, Timiyasu made a blunder that made City get the opportunity to create the seed first. Game-wise, the Gunners aren't too bad. unfortunately, several opportunities they missed.
As a result, City was able to take advantage of Arsenal's situation which was experiencing a crisis of confidence and made it a win for The Citizen. this defeat, had to bury Arteta's mission to win a trophy in this competition. otherwise, Arsenal will find it difficult to focus on the Premier League trophy.
For Barcelona vs United, on paper Barcelona is one level above The Red Devils. but at least, this fight will be very exciting for us to watch.