Yanez, 17, made his Real debut in midweek in the Champions League defeat at Liverpool.
And after Saturday's 3-0 win, he said: "Playing with Castilla was also a great dream and then they called me to come here to Girona and with more enthusiasm than ever.
"I should do what I know, what I do with my team."
The Cadiz native expressed what it means to him to play in the first team: "I've been dreaming about this for a long time, since I was born I was a Real Madrid fan and since I was little I've said that this was my dream.
"It's been a very positive season for me, I work every day as hard as I can for moments like this and I hope there are many more to come."
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