Kostas Manolas explained the switch to three at the back and assures Roma “are not here to defend a 2-1 lead” against Porto.
The second leg of the Champions League Round of 16 kicks off at 20.00 GMT at the Estadio Do Dragao.
“We want to be different and go through to the next round, that’s what we are here for,” the defender told RAI Sport and Sky Sport Italia.
“It’s a fiery atmosphere, but we are ready for it. We’ve opted for a three-man defence to get some more balance, as that is something we’ve lacked this season.
“It wasn’t exactly a surprise, we tested it out in training this week. We’ve been conceding avoidable goals and had to do something.
“Porto are a tough opponent who have experience in the Champions League, fight for every ball, but we are ready for them.”
Roma won the first leg 2-1 at the Stadio Olimpico, but have not kept a clean sheet on their Champions League travels for 12 years, conceding 74 goals in 31 games.
“We didn’t come here to defend a 2-1 lead. That’s not what the three-man defence is about. We’ve come here to take the initiative.
“The Coach told us we need a great performance, he is convinced we’ll do it and so are we. It’s important to have the same determination we had in the first leg.”
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