Gary Johnson has warned that more dissent from the stands could have a detrimental impact on his Bristol City players.
The Ashton Gate boo-boys made their feeling known on Saturday in the 4-1 home hammering by Reading, when Johnson made the second-half substitutions of Lee Johnson, Ivan Sproule and Nicky Maynard.
Johnson feels certain individuals could suffer if they let the crowd get to them and wants all the supporters to stand united behind the team.
He told the Evening Post: "If they're not careful, we are going to lose some of our players in terms of confidence.
"It could be a couple or it could be quite a few and, when that happens, it becomes dangerous."
Johnson added: "This group of players has done a fantastic job. I think some of our supporters have forgotten that.
"I don't know whether or not it's those who have recently jumped on the bandwagon and are used to seeing Bristol City win every week and being promoted.
"But they have to realise we're not going to win every game in the Championship and they can't expect us to be brilliant every week.
"Of course we're all disappointed when we don't play well, but people have to remember where we've come from."
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