The Manchester United forward was sent off for two bookable offences during his side's 2-0 defeat and although he exchanged words with referee Phil Dowd after being shown red, the official has confirmed he was not sworn at by the player.
The FA will write to Rooney however to issue him with a formal warning about his conduct after he punched the corner flag while leaving the pitch.
An FA spokesman said: "We have clarified with Phil Dowd that there was no abuse from the player after he was dismissed.
"In relation to the incident when he punched the corner flag, the referee did not see that and we have written to Wayne Rooney reminding him of his responsibilities."
It means Rooney will only be suspended for one game, the Premier League visit of Aston Villa to Old Trafford on April 5.