Boateng saw red for an aerial challenge with Morten Gamst Pedersen in the first half.
Brown is now launching an appeal against the sending-off.
"To say it is a nonsense is an understatement," he said.
"The problem I have with it is he had two to three minutes to make the decision while George was knocked out.
"But the players told me he already had the red card out of his pocket within seconds of the incident.
"It is clearly a clash of heads and a brave challenge by both players. If I am going to jump I am going to bring my arms up.
"If you look at George Boateng's history, he's had 14 years in the Premier League and two red cards. It is a good career record for me for a combative midfielder whose involved in tussles and tackles."