Manager Rob Page has called Port Vale's second-half performance in their 4-2 defeat by Chesterfield "comical" and labelled the goals they conceded as the worst he has ever seen.
The result almost certainly ended their League One play-off hopes with the club 10 points off sixth place with five games left to play.
"No-one should accept that display," Page told BBC Radio Stoke.
"It was an embarrassing second-half performance and it will be addressed."
Despite admitting their chances of finishing in the top six were slim, Page was optimistic at the Proact Stadium with his side leading 1-0 at half-time.
But he was left livid by what happened after the break.
"I told them at half-time to go and finish them off but to expect them to start fast and do not concede early. It went in one ear and out the other," Page said.
"After a minute, it's one-all. They are four of the worst goals I've ever seen. They haven't had to worked hard to score them, they're errors.
"It was comical - a comedy of errors - and I can't accept that."
Comfort in rivals' woes
With Vale's promotion hopes looking over for another season, their fans could take some comfort from the role they could play in the plight of their local rivals Crewe Alexandra.
Vale would relegate the Alex if they beat them at Vale Park on Saturday, Fleetwood Town win against Peterborough and Blackpool get at least a point at home to Colchester.