Gyokeres will lead Arsenal's line against his former club in Lisbon for the first-leg in their Champions League quarterfinal.
The Sweden centre-forward left Sporting in bitter circumstances over the summer and Arteta says he is ready to face his former teammates.
Arteta said, "I think he's very excited. Obviously, he's full of gratitude for his time here. The way he talks about the club, the players, the staff, everybody around the club. The experience that he had, how important that part of his journey in Sporting has been.
"And now it's Arsenal, it's a quarter-final of the Champions League, he's never played at this level in the competition and obviously you can imagine what it means to him."
Gyokeres goes into the clash having proved Sweden's matchwinner in their World Cup playoff final against Poland.
Arteta continued: "Those are experiences that you put in your veins, I would say. It doesn't get much better than putting your country into a World Cup with a goal that you scored.
"That's still there and that's going to be there for the rest of his career, like all the moments that he had here, the moments that he's creating for us. That's the story that he's creating and hopefully tomorrow he's going to show another very good side of him."
Asked if Gyokeres has met his expectations in his first season, the manager added: "I think it's where he is and how successful this season is going to be for us and when we analyse his season, it's going to be defined in the last seven or eight weeks of the season, that's clear."