Adam Flanagan apologised to the Dartford supporters who travelled to watch Saturday's humiliation at Eastbourne.
Joint-boss Flanagan described their 6-0 defeat in Sussex as one of the worst Darts performances he's been involved in.
Flanagan didn't hold back in his criticism of the players after they were mauled by a team battling against relegation.
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He said: "It's one of the worst Dartford displays I've ever seen, either playing or in the short time we've been managing here.
"A few players showed they're not good enough to be at the club. They haven't got the heart or the passion or the desire to want to win games and want to achieve good things and that was evident today out on the pitch.
"We've got a few players who have already got their minds elsewhere or the season ending and that's a crying shame to everyone who travelled down."
There was no quality to Dartford's play at all but the lack of fight once they'd fallen behind was a far greater worry.
"It was very concerning," Flanagan said. "We've got seven players who have disappeared in the last two weeks through injury or other various bits and pieces and six of those might have started. When you've got 50% of your team not playing, it's easy to find an excuse but there is no excuse for today.
"It's not like we played under-18s, there were a lot of seasoned players at this level and they should have more than enough about them to be beating teams at the lower end of the league.
"In the last few weeks, those players have had opportunities to showcase what they've got and these are players that haven't maybe started as many games as they would have liked but their overall performance was inept.
"The thing that hurts me the most is the lack of passion for themselves as individuals to want to beat the player they're playing against and the lack of passion to want to push this club forward.
"Our fans expect the mandatory requirements of working hard and showing desire and passion and playing for the badge. They've always had teams that have had that but for the last few weeks, we haven't shown it.
"The way it's gone in the last six weeks, injuries to one side, is massively concerning. For me, it's an issue that's within the squad.
"Me and Jamie are honest and we'll hold our hands up and I've gone in there after the game and I'm looking myself, thinking today's our fault. We didn't recruit well enough.
"We thought, after February, that we had a strong team who were hungry to push Dartford on and achieve big things but after today's show, I massively question that.
"We've got Billericay on Monday, they're a level above Eastbourne and from today's showing, I'm massively nervous. That shouldn't be the case."
Flanagan and joint-boss Jamie Coyle are bound to come under fire, especially if Dartford fail to make the play-offs.
Flanagan said: "You always have to look at yourselves. If you want to become good as a player, you've got to break your game down, analyse what you did or didn't do well and take it from there. As managers, we want to be successful and kick on and achieve good things so we look at ourselves every single time.
"We lost Macca (Darren McQueen) this week to injury and he might not have made a difference today but it added to the injury list.
"Being truthful, we're feeling a little bit sorry for ourselves because we're thinking if we've got everyone fit maybe the outcome of these games is a little bit different. But our final position in the league this year was never going to be dictated by today and the next two games, it was dictated over the last six or seven and we haven't been good enough.
"I don't think we deserve to be in the play-offs.
"Injuries to key players don't help but did I think we'd come here today and lose 6-0? Definitely not.
"Whilst we're accountable, the players have to step up and take the opportunities they get. There's probably players in there who feel they should have featured more throughout this season but they've had opportunities in the last few weeks and they've not shown enough."
Joe Healy won't be available for the Billericay game but there's a chance Charlie Sheringham could be fit enough to play some part.
Ronnie Vint, meanwhile, is a doubt after coming off 45 minutes into his comeback from injury.
Flanagan said: "Ronnie said he was fit to play today but, in my opinion, showed nowhere near the Ronnie Vint that we know.
"We are, unfortunately, bare bones but what can we do? We'll put the team out as best we can.
"You have a squad for a reason, there's players that are Conference South players and they should offering more than they're showing.
"We need to stop the rot. We've not won in a series of games now (six) and off the back of three losses, we need to turn up against Billericay on Monday and show 100% more than we showed today."