The chance of Arsenal qualifying to the next round is slimmer compared to that of Porto. Porto is very strong and seems difficult to win recently, we saw that in their recent games. Arsenal is equal to the task but only if the can score more goals than Porto at Emirate tomorrow that is what will give them the best chance of qualifying.
Hey, if Porto chooses to settle for a draw then it will be difficult for Arsenal since drawing the match will send Arsenal packing out from the league. If Porto draw, they win. If Porto win the match, it is a win win, but if they lose 1-0 to Arsenal, they still have hope. It is only if they lose with two goals gap that Arsenal is free. If Arsenal draw a the match, they are out. If the lose the match they are out, if they win without two goals difference it is 50-50 odds that they are will stay or get out of the league.
The biggest challenge for Arsenal in the second leg is that Porto can play very well in defense, and Porto have the advantage, the main thing for them is not to lose this match. Arsenal have matches when they score a lot of goals, but this happens against not the strongest teams, and as the first match against Porto showed, their attack is not so effective against a strong defense. Apparently Conceição was able to find a way to isolate the Arsenal attackers, as they were unable to make a single shot on target in Porto's goal.
There is no doubt that for Porto this will be a difficult match, there is also no point in denying that Porto has an excellent defense, and in the second match the guests will focus on defense, and if they manage to score a goal, then this will be their task for this match at most.