Michael Jolley was fuming with Grimsby Town's second half performance which saw them lose 4-0 at Coventry City.
Jolley told the Grimsby Telegraph:“Today’s second half performance was not of the required standard.
“I think that’s clear to everyone. I heard our supporters at the end and I can understand why they’re unhappy.
“I’m very unhappy, I’ve just made the players aware that I’m very unhappy. What we produced in the second half is not good enough, and if we continue to produce that, then we are going to have a very difficult situation.
“That said, Coventry away is a difficult fixture for anyone in League Two. What we have to do is regroup, and come up with a way of getting some points in the game on Friday against Stevenage.
“I don’t know exactly what the fans are saying, but if I’d been one of the fans today I would have been upset, particularly with our second half performance.
“That’s how I feel as a manager standing and watching the second half. I don’t feel we did enough to get anything from the game in the second half.
“We had a game plan which the lads did fairly well with in the first half, and I felt we were right in the game.
“But the way we enabled them to counter-attack on us and we lost our shape in the second half is not what we’re about at all, and I’m very angry about it, and the players understand I think.”