Benfica are capable of overturning their 2-0 first-leg deficit against Inter by scoring three goals at San Siro, according to midfielder Chiquinho.
Nicolo Barella's 51st-minute header and Romelu Lukaku's penalty in the 82nd minute earned victory in Lisbon, ensuring Inter are big favourites to advance from the Champions League quarter-final tie.
Benfica outshot Inter (12 to nine) and finished with a higher expected goals value (1.7 compared to 1.6), yet they now have it all to do in next week's return fixture in Italy.
But Chiquinho remains confident the Primeira Liga leaders, who lost for just a fourth time all season – two of those losses coming in the past five days – can still progress.
"We knew it was going to be a difficult game against a team with quality," he told CNN Portugal. "The game was even. We had our opportunities to score and we didn't.
"Inter managed to score twice, but nothing is lost. We're going to Milan and we're going to do our best to win.
"If they've scored two goals here, we're also able to go there and score two or three. That's why we're going there, and we're going to give it all we've got."
Benfica finished above Paris Saint-Germain and eliminated Juventus in the group stage, which they went through unbeaten, before thumping Club Brugge 7-1 in the last 16.
The Portuguese side are now without a victory against Inter in four encounters, drawing one and losing three of those.
Substitute Lukaku put the seal on Inter's latest triumph on Tuesday with his late penalty at Estadio da Luz, awarded after Joao Mario handled Denzel Dumfries' cross.
However, Benfica head coach Roger Schmidt felt his side should also have been awarded at least one spot-kick by English referee Michael Oliver.
"Losing at home is of course not perfect, but it's just the halfway mark," he told Eleven Sports. "You always have to believe in yourself.
"We had our moments and were unlucky with the penalty. We could have had one or two in our favour. They were more effective than us and next week we must try the same.
"We stayed in the game and the players gave everything. We created chances but conceded a second goal from the penalty spot. That's the story of the game."