Hernandez has made a fast start to his Reds career, impressing in pre-season and making his Premier League debut as a substitute in the 3-0 win over Newcastle.
He said: "It is like a dream. I am living the dream that I had when I was 10 years old when I loved this team and these players like Giggs and Scholes. I wanted to be like them.
"When I was young I always liked this league. I always wanted to play here. I am very happy I got this opportunity. I also want to open doors to players in Mexico to allow the important teams over here to look at other players from my country.
"I am here now and I want to enjoy it a lot and take this opportunity and to grow up as a human and as a player. Most importantly, I want to win things.
"To all the fans in my country and over here I want to say thank you for all the support.
"I can promise I will work hard and do my best."