Ruben Micael has warned Arsenal that Porto will not shut up shop in the UEFA Champions League and are ready to cause an upset.
Jesualdo Ferreira's side hold a 2-1 first-leg advantage in their last-16 clash ahead of Tuesday's return meeting at Emirates Stadium, but their hosts remain confident.
The Gunners only require a 1-0 win on home soil to progress on away goals to leave Arsene Wenger's men with far from a mountain to climb.
However, Micael insists Porto are well aware of the danger of simply defending their lead and they have no intention of sitting back against their hosts.
"To play defensively in our own area is not our plan because in these conditions it is impossible to stop the attacks of Arsenal," said the midfielder.
Porto have had a disappointing domestic season and sit 11 points adrift of leaders Benfica in the Portuguese top flight.
Micael, though, does not believe that misfiring form in their homeland will necessarily mean the 2004 European champions will struggle on the continent.
"In the Portuguese League we are not in our desired position, but this is not significant in the Champions League," he said.
Micael is also cautious about the absence of Arsenal's Cesc Fabregas and does not think the Gunners captain's hamstring injury is necessarily an advantage for Porto.
"The absence of Cesc Fabregas does not guarantee our success. I think that it could also be negative as his replacement will be at 100 per cent fitness."