Jon Brady described Port Vale’s last-gasp 1-0 Sky Bet League One defeat by AFC Wimbledon as “not good enough”.
Substitute Callum Maycock netted the Dons’ 88th-minute winner with his side’s only shot on target.
Defeat leaves bottom-of-the-table Vale 10 points from safety, having scored only 20 goals in 27 league outings.
But Brady revealed that former Championship Golden Boot winner Andre Gray could be in line for an earlier debut than expected.
“To concede and not defend the width of our goal was not good enough,” said Brady. “To switch off in that moment was so bad because we had defended brilliantly before that.
“It is so simplistic how we should have defended it. They didn’t have to work hard to get through us.
“We were in the ascendancy in the second half but we gave them the goal. But we have got to pick ourselves up.”
Brady said former Watford, Brentford and Burnley marksman Gray will have a medical on Wednesday and could feature in Saturday’s home clash with Burton.
“We have got to make sure everything is OK to see whether he can start or whether he comes on,” said the Vale boss.
“He is a goalscorer and we are probably the lowest scorers in the EFL. We are trying to change that and hopefully we have got a bit more quality now.”
Maycock’s strike – his first in the league this term – earned Wimbledon a first in four games to the delight of manager Johnnie Jackson.
“You can’t really beat a late winner especially the type of game it was,” he smiled. “It was in the balance.
“I thought we might have a moment in us. But they had a threat as well in the second half so you are making sure you don’t lose it.”
Maycock’s calm angled right-footed finish came from Alistair Smith’s assist to register his first league goal of the campaign.
“I was hoping we might have a moment and the goal was a real bit of quality. It was a good ball from ‘Smudge’ and Callum popped up in that little pocket and was really calm with his finish.
“It didn’t leave them a lot of time to get back in the game which was great. It was a brilliant end to the game.
“Cal has shown that before. He was probably unlucky not to start the game but we have got those options in midfield and decided to use him from the bench.”
