Eunan O'Kane saw red for Leeds United on Saturday.
The Republic of Ireland midfielder was given a straight red card on 37 minutes for allegedly nudging his head into that of Jonas Knudsen, and left the field without any protest.
Leeds boss Christiansen defended his man in the post-match interview and suggested that an appeal might be forthcoming, but O'Kane and his team-mate's reactions to the incident - or lack of reaction - suggest that they had no complaints over the decision.
And although Phillips says that the Irishman didn't have much to stay, the Leeds man claims he is very disappointed over what happened nonetheless.
Asked what O'Kane has said about the decision, Phillips said to West Yorkshire Sport: "He's not really said much. He's just a bit gutted about the decision obviously and we'll speak about it tomorrow at training."
Bersant Celina struck the winner on 67 minutes and Leeds can feel a bit unlucky to lose, despite only having 10 men for 53 minutes of the game.
Christiansen's side still created enough chances to leave Portman Road with at least a point, but it wasn't to be.