The Brazilian received his marching orders following a collision with former Vale man Harry McKirdy in the penalty area in which he was adjudged to have impeded the forward, leading to Covolan conceding a penalty and earning a straight red card.
At the point of this incident, Vale were level at 1-1 but due to the penalty being converted by Ben Gladwin, it was always going to be an uphill battle for Vale to try to find themselves a way back into the game.
This proved to be the case as they struggled to create anything of note and Nathan Smith's own goal with 21 minutes remaining ensured that the Robins would run away with all three points.
"He has let his teammates down"
After the game, when speaking on the sending off it was clear that Clarke was not happy with Covolan's actions.
"I am not happy,” he said.
“He knows how I feel but I don't want to hang out a lad to dry. He has let his teammates down today and he will be punished for that.
"He has caught the ball and kicked out. It is a stupid decision, there is no need to do that.
"That is not taking away that first half we were nowhere near it but I would have been changing things at half time to make sure that we was second half.
"I would have changed the shape, but that went out of the window, so it wasn't to be."
"He will learn from that"
The 44-year old continued: "It is very quiet in there because the manager is very heated. I don't like being let down, particularly like that.
"If you are going to get sent off, get sent off in a proper tackle. I think there was no reason for him to do it, he has caught the ball.
"It is a lack of discipline and he will be punished for that. He will learn from that, he has got to learn from that because otherwise he will not be staying at the club very long.
"That is the way I look at it, for an easy decision like that and every point counts in this league. Every decision players make count, every decision I make count in this league and he has made a decision today."