Brighton boss Roberto de Zerbi was delighted after their 1-0 win at AEK Athens.
An early second-half penalty from Joao Pedro saw Brighton win their Europa League tie 1-0 in Greece.
De Zerbi said, "We feel great emotion.
"We didn't play well, we didn't play in our usual style. It was a tough match. We showed a different mentality tonight, showcasing our soul and resilience.
"It was an historic day for Brighton, for the club and our fans.
"We are not used to winning in this way. Usually we lose games despite playing better than the opponent – just the way AEK lost tonight.
"Today AEK were better that us, but for once we won such a type of match.
"Now our ambition is to top the group. We have to defeat Marseille – and they are a great team, just like AEK."