Herrera appeared to handle the ball in the build up to the first goal before setting up Marcus Rashford to finish low from an angle.
Herrera fired in the second himself, via a deflection off Kurt Zouma, to dent Chelsea's title hopes and secure a 2-0 win.
Manchester United star Ander Herrera insists he didn't intentionally handle the ball against Chelsea
And after the own he insisted he had no intention to handle the ball in the build-up to United's first goal.
"If you don’t have the intention to touch the ball and your hands are in a natural position it is not a handball," Herrera told Sky Sports.
Manchester United player ratings against Chelsea Sun, April 16, 2017
Express Sport rates how the Manchester United players performed during their win over Chelsea at Old Trafford
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Which Manchester United players impressed during their win over Chelsea?
"It was almost perfect, defensively it was perfect and they didn't create any chances.
"In the counter attack we hurt them and controlled the game and moved the ball well.
"I have been looking for a goal for a long time. Today I was a bit lucky, but I think we deserved this."
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