Arsenal crumbled in the first leg in France after a first half red card to Sokratis Papastathopoulos and now need to summon even more character than it took to overturn a smaller aggregate deficit against BATE Borisov in the previous round.
"We are very demanding of ourselves," Emery told a press conference, via Arsenal.com.
"For us, it's one positive issue because we want to play big matches, tough matches against the best teams - and in the Europa League we are finding some results like the last round against BATE Borisov with difficulty," the Spanish coach added.
"I want to play matches that are difficult, with difficult results or with difficult players.
"We need to be together and create a big atmosphere in the Emirates with our supporters to help us to do the best performance possible in 90 minutes. We need to play with high emotion with our supporters but taking decisions on the pitch cleverly with our mind.
"This is both important issues that we need to control over 90 minutes and maybe more."
Sokratis will be suspended, but Arsenal will have Alexandre Lacazette back earlier than expected after his UEFA ban was cut on appeal and midfielder Lucas Torreira hopes the French forward can help make the crucial difference on the night.
Source : 90min