The forward scored in an impressive 2-1 win over Manchester City over the weekend.
Semenyo was a constant menace to the City backline, while forward Evanilson got the other goal in the game.
Asked about Semenyo, Iraola stated post-game: “He has been playing very well all the season.
“I think we demand him a lot because I think he can give a lot, and today probably he scores and everyone gives him more recognition.”
He then added: “I think Antoine is going to be always dangerous for every center back, every full back that he attacks.
“But it was more defensive minded because we decided the job defensively that the right winger had to do was more difficult.
“Normally Tav (Marcus Tavernier) is very good tactically interpreting these kinds of difficult situations, and that was the main reason.”