A double from teenage midfielder Nicolo Zaniolo looked to have put Roma into a strong position in last month's first leg, only for a late effort by Adrian Lopez to leave the tie in the balance.

Di Francesco, though, maintains any uncertainty over his position must not impact on Wednesday's game.

"My future isn't important right now; what matters is qualification for the last eight," he said at a press conference.

"We have to focus on maintaining our advantage and start again. We need to get our defensive game just right, the rest will take care of itself.

"We are having a tough time. The derby has damaged morale, but this is a bit of a game of life or death."

The Giallorossi, who qualified as runners-up in Group G behind Real Madrid, are without winger Cengiz Under and playmaker Javier Pastore because of injury.

Defender Kostas Manolas, who was laid low by a virus, and Zaniolo, the 19-year-old carrying a hip problem, have both travelled.

Di Francesco confirmed his side will line up in a 4-3-3 formation, but gave little else away over his starting XI.

"I want to decide, in the end, by looking into the players' eyes and seeing who is most ready for battle," he said.

"It's vital that we go out there with players who are clear-headed, focused and ready to show what the real Roma is like."

Sergio Conceicao's men come into Wednesday's game on the back of a home defeat by domestic title rivals Benfica – a first loss in the Portuguese top flight since being beaten away at Estadio da Luz back in October.

Porto have not won a Champions League knockout fixture in six attempts.

The Dragons, though, progressed unbeaten at the top of Group D ahead of Schalke, with victories in all three of their home matches to reach the last 16.

Conceicao wants his team to be patient as they look to overturn the one-goal deficit and bid to reach the quarter-finals.

"We need to win the game, but not so quickly," he said.

"We have to be at a good level defensively. Roma have the third best attack in Serie A, balance will be essential to get the win.

"There's no need for a battle-cry, the game is in our hands.

"If we are true to ourselves, then we have a great chance of progress."

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