Aston Villa will appeal against the red card shown to Chris Herd in Saturday's 2-1 defeat by West Brom.
Midfielder Herd was sent off following a tangle with West Brom defender Jonas Olsson.
Referee Phil Dowd dismissed Herd after his attention was drawn to the incident by his assistant and McLeish felt guesswork was involved.
Villa had been leading 1-0 at the time of the red card and McLeish is adamant that Herd did nothing wrong.
He said: "It's a poor decision on the day by the official. These things are not deliberate - he's made an honest mistake.
"It's a shame that he's guessed the decision, rather than seeing anything.
"No doubt about it, looking at the pictures again Chris has done nothing wrong."
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