Marca says the 22-year-old, who can play both as at centre-back or as a left-back, has joined the Pepineros for the next four seasons.
Hernandez has already trained with his new team, after passing his medical and he will be officially presented in the coming days.
He made his debut for Los Blancos' youth side in the UEFA Youth League in 2016/17 and debuted in the Segunda B the following year.
Need a VPN? Or seeking to switch? Then support Tribal Football by clicking here to sign up with our official partners NordVPN. Not only will you receive the best VPN experience, but also great discounts by signing up via Tribal Football. Thanks for your support!