Lyon, who slumped to a surprise 2-1 home defeat by strugglers Caen in Ligue 1 on Saturday, have developed an eye-catching style of play but often get hit on the counter-attack.
"We concede too many goals, which makes our games more complicated because we need to score two or three to win," France keeper Lloris told a news conference on Monday.
"If we're not rigorous, we'll be in trouble. They sit back and make the most of their counter-attacks. They're typically the kind of side that can score against us.
"We have seen that when we fall behind against a team that defend deep on the pitch, we struggle to come back."
Lloris reckoned the key to reaching the last eight would be not to concede at home.
"Let's start by not conceding a goal, and possibly let's try to win the game to make it easier for ourselves for the return leg," he said.
APOEL, who qualified top of a group featuring Porto, Shakhtar Donetsk and Zenit St Petersburg, firmly believe in their chances of another upset.
"They are clearly a bigger club than us with a much bigger budget and better footballers but that doesn't mean anything as we have shown that a small team can reach the knockout stage of the competition and do just as well in this next stage," APOEL captain Constantinos Charalambides told uefa.com.
"I am convinced we can do to Lyon exactly what we did in our group to Shakhtar, Porto and Zenit. I believe in this team and with the right approach and a little bit of luck, why not?"
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