Chelsea FC took the lead in the 36th minute at Stamford Bridge thanks to Cesar Azpilicueta’s close-range finish.
However, West Ham fought back when substitute Hernandez fired home an emphatic finish in the 72nd minute.
And the Blues were unable to find a winner as they suffered another blow to their hopes of Champions League qualification.
It was the sixth time that Hernandez has come of the bench to score against the west London side.
And the Mexican striker had a cheeky message for Blues fans after the game.
Speaking to Sky Sports, Hernandez said: “I’m sorry to Chelsea fans but sometimes it happens.
“It’s difficult because I don’t want to speak bad about them. That’s part of football.
“Sometimes I cannot score against another team and sometimes I keep scoring against Chelsea for example.
“The most important thing here is that we get one point and keep adding points to fight relegation.”
The result left Chelsea FC in fifth place in the Premier League table and 10 points behind Tottenham with just six games left to play this season.
They will return to Premier League action next weekend with a trip to Southampton next Saturday afternoon.
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