The wing-back collected his fifth yellow card of the season against Aldershot Town and, as a result, he has been handed a one-match ban.
FA records show the 26-year-old was booked in the first-half for ‘adopting an aggressive attitude’.
Saturday was the cut-off point for five yellows so had King avoided going into the referee’s book he would not have been suspended.
King has scored two goals and claimed one assist in his last three games so he will be a big miss for the Blues. His absence could mean Tyrone Williams moves to right wing-back and Fraser Kerr could come into the back three.
Curtis Weston was another player on four yellows and at risk of suspension but he was not booked.
The cut-off point for 10 yellows and a two-match ban is 37 games. Striker Stefan Payne, who has seven yellows, is the closest to reaching that mark.