Martinez hit with improper conduct charge
"The charge relates to media comments made about referee Stuart Attwell following Wigan's match against Manchester City on 29 March," the FA said on its website.
Spaniard Martinez told reporters after his defender Gary Caldwell was sent off that "we're all human beings and make mistakes but to give a decision out of something you didn't see, that's lying".
He has until April 22 to respond to the charge. Wigan lost the game 3-0.