I'm wondering what Arsenal will do as of this stage in the Champions League. They had a successful group stage as expected. Now I can say that they have a comfortable matchup to play against Porto as well. Because I don't believe Porto are one of the teams that can eliminate Arsenal in this tournament. Porto couldn't even beat Barcelona in the group stage. I mean that Barcelona aren't weak of course but I don't think they have played better than Arsenal at all. 
Anyway I see Arsenal in the quarter finals already to tell the truth. But they had better improve their performance more as there is some decline recently.
When Arsenal was drawn against FC Porto in the round of 16 of the UEFA Champions League, I expected Arsenal to win against FC Porto but with the recent performance of Arsenal, I'm not sure if Arsenal could be able to beat FC Porto. If FC Porto can play well in their home, I believe they will beat Arsenal. Anyway I see Arsenal in the quarter finals already to tell the truth. But they had better improve their performance more as there is some decline recently.
Who knows what Arsenal will play next with their opponent Crystal Palace and we can use this match to determine the strength of Arsenal against Porto, let's see if the return of Timber can help the team until then.