Fatih Terim fired a warning to Galatasaray's Champions League rivals following Wednesday's 2-1 win over Braga.
The Super Lig holders were heading out of the competition after falling a goal behind, while Cluj held on for victory over Manchester United, but Aydin and Burak Yilmaz both scored to send the Turkish giants through to the last 16.
"I can't say much about our performance but I am happy with our desire to win and I congratulate the players," Terim said after the match.
"I'm very pleased that we completed the job on our own instead of waiting for help elsewhere.
"Earlier I said 'we haven't had our final word, there's more to come'. You see, Galatasaray still have plenty to say in Europe.
"It is a long road, but we'll try anyway. If we encounter a hitch, we'll try again. With the help of our fans, we can do this."
Terim then proceeded to thank Galatasaray's fans for their continued support, and revealed his belief that the result had united the squad.
"I want to thank our fans," he added. "They watched us late into the night, sacrificing their sleep.
"With their prayers and positive energy, we created a thing of beauty. To be honest, we didn't play well in the first-half.
"I think the players thought Manchester United might beat CFR Cluj. When you go 1-0 down and get the news that Cluj are 1-0 up, it's not easy to overcome that.
"Some games make a team a real team. Some matches unite our communities, even whole countries. Some just go downhill."