Vale slipped to a 2-0 home defeat to Bolton Wanderers on Saturday afternoon in Sky Bet League One action.
The dismissal of Riginio Cicilia had a huge impact on proceedings in the view of manager Michael Brown.
He said: “It was another extremely disappointing day for us, I thought we came out and tried to put them on the back foot and we were excellent at times against a good Bolton team.
“The red card changed the game. Riginio has put his arm up to go feel for the defender, he is six foot five so his arm is going to be high and the ball just misses his head and hits his arm.
“The referee doesn’t take time to think about it and it’s a very disappointing decision which changed the entire outlook of the game. Even their bench didn’t appeal, it was a big call.”
Despite the result, Brown couldn’t fault the effort of his players who matched Wanderers for large parts even with a one-man disadvantage.
Jerome Thomas struck the post early in the second half and the manager insists that reflected Vale’s luck.
He said: “I thought they were great. When that doesn’t go in you begin to question if it’s your day.
“It was still a very good performance, and maybe there was a foul on Andre Bikey in the build-up to Bolton’s second goal.
“Up until that moment I thought we were excellent even with ten so full credit goes to the players and they are the positives we take.
“We have got to go and do that again on Tuesday.”