Courtois, who joined in a £35million deal from Chelsea over the summer, shone in the goalless Madrid derby against crosstown rivals Atletico on Saturday.
Denying Antoine Griezmann and Diego Costa, the Belgian made a series of key saves to preserve a clean sheet as Real kept pace with Barcelona at the top of the La Liga table.
Question marks have been placed over Courtois’ footwork, but the 26-year-old strongly refutes this is a weak area of his game.
“I’m not bad with my feet,” he said.
“I may not be among the best, but I’m certainly not bad either. Sometimes I miss a long ball but I dare to play with my feet.
“The last ball on which [Nikola] Kalinic put pressure was given to [Raphael] Varane with my right.
“Many goalkeepers would have cleared that ball.
“Sometimes I give a bad ball, yes, but I know more goalkeepers who are, so to speak, phenomenal with their feet making more mistakes than me.
“I’m just doing what I have to do, and that’s the most important thing.”
Real travel to face CSKA Moscow in their second Champions League group game tonight (8pm).
And Julen Lopetegui is under no illusion that his side face a tough challenge.
He said: “We’ve got to continue on in the same vein: go out in every match to win and try to get as many points as possible.
“The setting is incredible and our opponents wanted the game to be staged here and so the atmosphere is sure to be excellent.
“We’re up against some fine players and it’ll be an extremely challenging game because this is the Champions League.
“The players’ mindset is excellent and we’re really raring and excited for the game to get under way.
“We face a strong side on their own patch and there’s no bigger motivation than that.
“When the Champions League hymn sounds, there’s no better motivator. We’re confident that we’ll be able to achieve our target.
“If they’re thinking that this is the best time to play us, we’ll have to see about that tomorrow.”