Merson wrote in the Daily Star: "Arsene Wenger was a disgrace for refusing to shake the hand of Roberto Martinez.
"Wigan totally deserved their win at the Emirates and Wenger was disrespectful.
"Martinez has been up and down the country getting beat all season.
"I bet he shook Martin O'Neill's hand when they were hammered at home by Sunderland.
"I bet he shook Sir Alex Ferguson's hand when they were smashed 5-0 at Old Trafford. I thought Wigan were an absolute certainty to go down."