Stephen Baxter said referee Shane Andrews' decision to send off Carrick Rangers goalkeeper Nathan Gartside in their European play-off defeat at Dungannon Swifts was "completely wrong".
With the visitors already trailing to Leo Alves' 21st minute free-kick, they were reduced to 10 men just after the half-hour mark as Gartside was adjudged to have handled the ball outside his box as the keeper cut out a pass.
Despite the setback, Luke McCullough drew Carrick level in the 38th minute, but second-half goals from Caolan Marron and Kealan Dillon secured the Swifts' place in Saturday's semi-final against Cliftonville at the expense of Baxter's side.
"The television will reveal that the red card should never have stood, the referee's got that completely wrong," said the Carrick boss.
"We should also have had a penalty in the first five minutes and he doesn't give it.
"It's difficult whenever you don't get these decisions going for you. It's hard enough to play 11 men when you're away from home but if you have to play for an hour with 10 it makes it all the more difficult.
"The referees clearly need help with making big key decisions, particularly in big games. I don't mind VAR, provided it comes in and it's used in the right manner as regards to all the competitions and everybody knows the rules and how it's all set up. All of those things are important."
Despite missing out on a potential European spot, Baxter is pleased with the progress his side have made this season as they ended their 33-year wait for a trophy by lifting the County Antrim Shield.
"I'm thrilled at the improvement," he added.
"There's lots of stuff going on behind the scenes that we've been working on for ages. It all just doesn't happen overnight. You're working hard to make these things happen.
"But it's disappointing because you put an awful lot of work into it all year round to get yourself into this position and to get done on a few decisions is never good."
