"Geoff is very disappointed," club captain Steve Vickers told the B'ham Evening Mail.
"He said it was a clumsy challenge, but there was no malice in it. He missed the ball but his studs got caught in their lad's sock and went down his shin, so it looked far worse than it actually was.
"Geoff isn't the sort of lad to deliberately injure a fellow professional."
And Blues goalscorer Paul Devlin echoed the skippers sentiments: "Geoff is a very hard player, a very strong player. He probably takes more knocks than anyone else in the team.
"I don't think he's got a malicious bone in his body. It was a miss-timed tackle, it wasn't premeditated. He doesn't go out to 'do' other players."
Horsfield's dismissal rules him out of the FA Cup tie against his former club Fulham (away) and the Premiership matches against Arsenal (home) and Blackburn Rovers (away).
Charlton Match Report
Charlton Match Photo's
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