Born in Caracas, Hernández played Spanish lower league and amateur football until the age of 25, competing mainly in the Community of Madrid. During that time, he represented CF Rayo Majadahonda, CD Guadalajara, CU Collado Villalba, Real Madrid C, Rayo Vallecano B, Real Jaén, Valencia CF Mestalla and Real Murcia, delivering a Man of the match performance on 26 October 2010 in a 0–0 home draw against Real Madrid in the round of 32 of Copa del Rey (1–5 aggregate loss); additionally, he represented SD Huesca in Segunda División in the first part of the 2009–10 campaign, but his input consisted of two domestic cup appearances.

Hernández made his debut for Venezuela on 7 September 2010, in a 1–0 friendly win with Ecuador. As a backup, he was part of the squad that appeared at the 2011 Copa América in Argentina.

On 19 August 2011, Hernández signed a 1+2 contract with Real Valladolid in the second level. He spent the vast majority of his first year as understudy to Jaime but, due to injury to his teammate, excelled in the promotion playoffs as the team returned to La Liga after a two-year absence, conceding only once in four appearances and three starts.