Neal Ardley conceded AFC Wimbledon's play-off hopes were all but over after they squandered a two-goal lead in their home draw with fellow promotion hopefuls Northampton.
Goals for Sean Rigg and Jake Reeves put Dons in command against opponents they had not beaten in seven previous attempts.
However, James Gray's double salvaged a point for the Cobblers.
Ardley admitted his side had always been a long shot and they were now all the more likely to come up short.
He said: "Our chances were slim anyway before today. To get to the 68-70 points you need to give yourself a chance we needed to win five and draw one of our last seven.
"So we now have to win five of our last six and we have not managed to do that all season, so it is a very remote chance.
"We will go hard for the rest of the season as that is all we can do.
''If the playoffs become mathematically impossible then the second thing for me is can we get above 60 points, can we get into the top 12 and can we give ourselves some momentum where we can say if we can improve on that next season, and we've improved every year I've been here, then we really will be in with a shout."
The game appeared to hinge on Craig Tanner's 63rd minute strike which hit the bar. Had that gone in Dons would have led 3-0 and the game would surely have been over.
However, Ardley rejected suggestions this had been the turning point, insisting his defenders should have been good enough to see the match out.
He added: "We were 2-0 up and there should not even be talk about if we had gone 3-0 up. I'm annoyed because we did not mark properly at a set piece. Everyone has got their players to mark yet it was too easy for them to score.
"It was not good enough. There was nothing tactical about sitting back. We still had three forwards on the pitch because I wanted to go 3-0 or 4-0 up, but defenders did not do their jobs."
