Arsenal manager Mikel Arteta was not happy with the referee after centre-back Gabriel got a second yellow card.
The Brazilian committed two bookable offences in quick succession in the second half and got his marching orders.
It meant the team had to play with ten men for 35 minutes, and could only manage a 1-1 draw with Southampton.
Asked about the red, Arteta told reporters: "I don't know. I was really disappointed with the two yellow cards - one on Dani and one on Gabi because there were many other incidents during the first half that didn't get a yellow card.
"Obviously that is going to affect your game.
"Then the second one, yeah. Exactly."
