City meet Al-Hilal in the round of 16 on Tuesday.
Reflecting on the tournament, Egypt international Marmoush said: “We’ve spent so much time together, sitting together at breakfast, lunch and dinner.
“Also, between sessions and after sessions we have free time that we’re spending together. That brings the chemistry up and makes us feel like a big family.
“We could be here for a month so having fun every day helps a lot to improve the chemistry and play better on the pitch.”
Al-Hilal full of quality
Marmoush also said of Al-Hilal: "Anyone can win the tournament and that’s why it’s so nice to be here because you play teams from all over the world.
“Al-Hilal are known as one of the best teams in Saudi Arabia and I think they’ve proved already in the tournament that they have a lot of quality.
“We respect all of the opponents but we know if we bring our qualities on the pitch then we will be very hard to beat.”