Glentoran boss Declan Devine felt Ballymena's match-winner Ben Kennedy did "a job on the ref" to get Marcus Kane sent off in his side's 1-0 loss at the Showgrounds.
The visiting skipper was shown a second yellow by referee Declan Hassan for a foul on Kennedy in the 74th minute with the former Crusaders man going on to score the only goal of the game against ten men.
"I don't think it's fair at all," said Devine.
"I'll save my judgement because I think the referee was conned.
"When the player is on the ground laughing in front of our dugout, you know he's done a job on the ref."
Devine also felt that Ballymena's Johnny McMurray could have been dismissed for a second booking shortly after Kane received his marching orders.
"There was another decision a few minutes after it when it was a second yellow card in my opinion that wasn't given.
"Referees have a difficult job but that decision, it was a really important decision and it hasn't helped us in any way."
Even playing a man down, Devine added that his side should have held on for a 0-0 draw at a "minimum" and was left frustrated by the nature of Ballymena's winning goal when Kennedy scored after a flick on from a Sean O'Neill goal-kick opened up the Glentoran defence.
"To lose in the manner we lost, from a straight goal-kick, it's nothing to do with being down to ten men, it's nothing to do with mistakes in the game or decisions in the game," he added.
"It's our game intelligence. That's where the frustration comes from."