Manager Lee Clark has been angered by Zigic's poor work ethic and attitude at the club's Wast Hills training base and has not held back in his criticism of the towering Serbian striker, who still earns a reported £50,000-plus per week following Blues' relegation from the Premier League.
Zigic, 32, has been used sparingly by Clark this season, making nine starts and 13 substitute appearances during which he has scored six goals. But he will not get the chance to add to that tally against Watford at St Andrew's, where he would probably have started with Marlon King unlikely to feature due to a knee injury.
Clark said: "I witnessed possibly the worst training session in terms of a professional footballer I have ever come across on Thursday. We did our preparation work for Watford and he (Zigic) was in the team. And I was disgusted when I walked off.
"I need to tell the fans before the game because obviously the social media network will go into overload because of this. I know he's quite popular.
"But ultimately he's a very well paid guy and you've got to earn that. And what he dished up yesterday was, since I've left school at 16 and been a professional footballer - not technically or tactically - the worst I have ever seen.
"And this is not the first time. This has been coming. There will be people who disagree and say this is a crazy thing. But what am I meant to do? Am I meant to accept that, just let people do that? All the other players see that. Or am I within my rights as a manager?
"Whatever happens tomorrow (Saturday), I can sleep soundly in my bed because I know I have made the right decision, in how Lee Clark goes about the football work and his business."
Zigic joined Blues from Valencia on a four-year deal for an undisclosed fee in the summer of 2010, with the highlight of his City career to date being his headed opener in City's memorable 2-1 Carling Cup triumph over Arsenal at Wembley in 2011.