Trabzonspor sit second in the Super Lig with 23 points, picking up 13 of those in Onana's six appearances so far - which also includes one assist.
Onana has been the subject of praise from Manchester City manager Pep Guardiola for his ability with the ball at his feet.
"As I always say, most of the time, it’s my teammates who give me the options when I’m building up the game," he told Sporx. "If they help me, the work looks much better.
“If I have to create a play, I analyse it first. Are the opponents pressing, are they pressing with their wingers, are they pressing with their strikers, or are their centre-backs coming forward?
“These are the things I need to see when I have the ball. I watch how the opponents are moving and then I look at the options and make my decision. Of course, it’s always great to hear a comment like that from Pep Guardiola. He’s one of the best managers in the history of football."