Having taken over from Paulo Fonseca in March, Castro is hoping that the Portuguese outfit can triumph in Europe's secondary club competition for the third time in 11 years.
And, as he prepares to face Sevilla in the first leg of his side's quarter-final tie on Thursday, Castro has revealed that he feels a duty to the fans to deliver a strong performance.
"Working at FC Porto is an act of responsibility," he said. "The Europa League is a prestigious event that FC Porto has won and wants to win again.
"It will be an extremely difficult game against a team that has a good streak. We are optimistic and hope to win the first part of this round without conceding. We are hopeful for a strong result.
"We are aware of the importance of this game and want to continue in the event of course. We have a very big ambition
"Sevilla have won eight of their last 10 games and are a team full of quality players, but we're focused on us and what we have to do."
Porto lifted the UEFA Cup in 2003, before winning its successor - the Europa League - in 2011.
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