Carlos Carvalhal questioned the second sending off in as many games for Fernando Forestieri following the forward’s dismissal at Hull.
Forestieri saw red for picking up two yellow cards, the second of which was questionable, said the Owls’ head coach.
The Italian was also sent off at Preston last weekend.
Carvalhal said: “For me it is a question of sense.
“I accept the first yellow card because there was a push but for the second I absolutely do not accept because there is a foul, there is contact and the defender knew this situation.
“Even if there was no contact, what is Fernando supposed to do?
“Sometimes to be safe you must jump out of the way for what could be a broken leg.
“In my opinion this was the wrong decision and we have suffered three bad decisions in our last three games.”
Forestieri will receive a mandatory two-match-ban, sitting out the home game against Rotherham on Saturday and the trip to Brighton four days later.