Referee Lee Mason and his assistants failed to spot a clear hand ball by Hernandez as he converted West Ham's equaliser against Fulham.
The Hammers would go on to win 3-1 last night.
Carragher told Sky Sports: 'His reaction was telling, how long he stayed on the ground.
"Week after week there's arguments, debates about diving, cheating, whatever it may be. That's exactly the same.
"He knows exactly what he's doing punching the ball in at the back post. Is it cheating? Is it gamesmanship? It's cheating. He knows exactly what he's doing.
"Would I complain if my own striker did it? Probably not.
"VAR would clear that up. It was a blatant handball from Hernandez and it's completely changed the ascendancy of this game."