The Mexican hit the winner 15 minutes from the end of an incident filled game against Chelsea at Stamford Bridge; it was United's first win on the ground for ten years.
And the player believes that the books are now being balanced after it was said that Chelsea had the edge over United this season and many tipping the Blues as Premier League title winners.
The victory also narrowed the gap on league leaders Chelsea to just one point.
"This game could have changed the title," Hernandez said to the Associated Press.
"That's why it was important we didn't allow them to get ahead.
"It was vital to get the three points at a very tough place. We are in there in the fight to win (the Premier League)."