Arsenal will need to overturn a 5 - 1 first leg loss against Bayern on Tuesday if they are to advance to the next round .
Barca will need a massive comeback against Paris Saint - Germain on Wednesday .
Arsenal will need to overturn a 5 - 1 first leg loss against Bayern on Tuesday if they are to advance to the next round , while Barca will need a massive comeback against Paris Saint - Germain on Wednesday .