West Brom coach Carlos Corberan expressed frustration following Brandon Thomas-Asante's red card in their 1-0 loss to Sunderland.
The English-born midfielder received two quick yellow cards in the first half, leaving the team with 10 men.
Corberan emphasized the importance of managing the situation, highlighting the impact on the game.
The loss was compounded by a goal from French-born Ghanaian midfielder Pierre Ekwah in first-half stoppage time.
Corberan noted the team's lack of experience playing with a numerical disadvantage and referenced a previous match where Sunderland's Dan Ballard injured his striker Josh Maja without repercussions.
“The second yellow card had a massive impact. You can have desire, but when you have a yellow card, you need to increase the calm,” Corberan said.
“To concede from a set-piece after losing a player is painful.
“If the referee understood it to be a yellow card, it has been our mistake to achieve two yellow cards. It’s a lesson for Brandon and it’s a lesson for us.
“We haven’t had the experience to play with a player less since I arrived. I know for some teams how much of a disadvantage it can be.
“For me it was unfair that in the first game, they injured Maja. It was a terrible action. It was unbelievable. The player (Ballard) who scored that day injured a player and the referee didn’t send him off or give him a yellow card.
“It was ridiculous – not just because it was against us, I am talking about football. If somebody today breaks their limits with two actions, they’re two yellow cards. When you have a yellow card, you must control yourself.”