(Click on image if it's not playing.)
Edouard Duplan was part of an embarrassing incident playing for FC Utrecht against Ajax in the Eredivisie.
The referee stopped play to tell Duplan to get off the pitch as he had been substituted. The player, who had been off the pitch receiving treatment for an injury, did not realise that he had actually been substituted. He kicks up a stink with the ref who manages to convince him to leave the pitch by pointing to his replacement, you can see the realisation dawn on the players face in the GIF above.
The player sees the funny side of the incident and makes his way back to the bench where he was subject to some abuse from his teammates.
GIF via Reddit