He won the heavyweight Junior World Championships in 2002 in Santiago de Cuba but lost twice to countryman Odlanier Solís and was forced to go down in weight.

At light heavyweight (178 lbs) in 2003 Hernández won the silver medal at the Pan American Games in Santo Domingo where he lost to Ramiro Reducindo.

There he was defeated in the second round of the light heavyweight (81 kg) division by Russia's Evgeny Makarenko, a double world champion in the event.

On March 13, 2010 Hernández made his first defense of the IBF Inter-Continental title by beating Cesar David Crenz by unanimous decision.

Hernández knocked Cunningham down with a counter left hook in the first round and seemed to be badly hurt, but referee Mickey Vann decided to let the fight continue after what seemed like a controversial slow count.

However the latter round was also marred with controversy as Hernández was hit with an accidental headbutt that caused a cut and that many felt was intentional, with referee Vann not stopping the fight or even giving a warning to Cunningham.