Arsenal manager Mikel Arteta was furious at the referee for not sending off Crystal Palace star James McArthur.
The Palace veteran committed a poor challenge on Arsenal’s Bukayo Saka after the latter cleared the ball from his own penalty area.
McArthur, who is 34, was shown a yellow card by referee Mike Dean, despite the recklessness of the challenge.
Arsenal finished the game with a point after a 2-2 draw at home against the side managed by club legend Patrick Vieira.
“It was a red card (for McArthur), absolutely,” Arteta told Sky Sports.
“I cannot understand how he can stay on the field.
“We had to take (Saka) off because he could not continue. He was very sore in the area.
“When I look at the action I cannot understand how the (Palace) player can continue playing.”