"It was an excellent experience," Merida told arsenal.com. "We see them [the first-team] play every week, and when you get to actually mix with them and have the possibility to come on, it's an honour and you feel very happy.
"I came on just for two or three minutes but it is still an excellent feeling and I was so happy."
The Spaniard hopes that his cameo appearance is not his only opportunity to play under Arsene Wenger.
"It's good to always be thinking about it, and aiming for the Carling Cup squad. The boss likes to bring some of us boys through into the first team, and we must work hard in order to prove we are ready for that level."