"We have delivered great performances in the Europa League. At 1-0 we had the necessary luck. Our tactical discipline was important and we absorbed the emotions of the audience."

Hutter also said he was relishing the prospect of facing Maurizio Sarri's Chelsea and stressed his own side's underdog status for the tie.

"We are perhaps the least anticipated semi-finalists, and Chelsea will be the favourites," Hutter added.

Benfica coach Bruno Lage, who was sent to the stands for protesting that Kostic's effort should have been ruled out for offside, said his side were left to rue missed chances.

In an interview quoted by uefa.com, Lage said: "I believe that, although we weren't as strong as we were in the first leg, we created enough opportunities to qualify.

"During the first half the pressure was not as strong as we wanted. In the second half we got better and we tried to go looking for the result, but unfortunately we failed."

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