An early penalty from Victor Osimhen was enough as Gala won 1-0 at the Ali Sami Yen.
Okan later said: "Winning is fantastic. The atmosphere was incredible, the boys played really well. They did everything we asked of them, from defense to attack.
"I also thank our fans, they never stopped cheering us on. We showed what Turkish teams can do, we won without conceding a goal against Liverpool. It's a victory that increases our motivation in the Champions League."
Okan also said: "After the match against Alanyaspor, we focused on this match. In the Champions League, every game is tough, and against an opponent like Liverpool, the champions of England, managing to prevail is a source of great pride.
"The team managed possession well, creating plenty of chances without conceding any dangerous ones."