Tensions came to a boil inside the Estadio Dragao, as Edin Dzeko squared up to the notorious Pepe before embarrassingly hurling himself to the floor.
The big Bosnian striker had been battling with former Real Madrid defender Pepe all evening, as Porto and Roma traded blows in hoping of booking a place in the quarter final stage.
Ultimately, it was Porto who would come out on top with a 4-3 aggregate victory, overturning a 2-1 deficit from the first leg.
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Pepe and Dzeko's fascinating battle continued to develop all night, before patience finally split and the pair squared up to each other on the field.
Getting right up in one another faces, Pepe appeared to scream 'F*** you' to Dzeko before foreheads were locked together.
After pausing for a moment, former Manchester City man Dzeko decided he would throw himself to the floor just as referee Cuneyt Cakir moved in to distinguish the situation.
If he was hoping Pepe would be sent off, he was soon left disappointed.
The Portuguese veteran stood aside and began to laugh to himself, while players from either side engaged in some more minor pushing and shoving.
One Dzeko had returned to his feet, the ref called both men over before brandishing a yellow to each.
The game played out and it was Pepe and Porto who would have the last laugh, following a penalty awarded deep into extra-time.
Alex Telles stepped up in the 117th minute of play, to hold his nerve and convert from 12-yards.
Porto join Manchester United, Tottenham and Ajax who have each booked their place in the last eight of the competition.
Hosbiprtuz
1
dont mess with pepe
Portoguese
2
Pepe is a tough modafoca