Nick Haycock felt the Development Squad were lucky to escape defeat after watching his side surrender a two-goal lead in a 2-2 Barclays Under-21 Premier League draw with Leicester City at Rush Green on Friday night.
Paul McCallum got the hosts off to the best possible start after only two minutes when he bundled home from a George Moncur free-kick.
Elliot Lee then doubled the lead with a penalty just before half-time but the Hammers went onto concede twice in the second period and Haycock felt things could have got even worse.
He told West Ham TV: "I thought we deserved to lose the game. Without making any excuses I thought they were the better team in the first half as well.
"We scored early but didn't assert our authority on the game like we normally do and I think we just sat back at 1-0 up and thought we were going to coast through the game. We got the penalty before half-time and in the first half we had the better chances, we hit the post as well so we probably created more.
"I thought their shape was good, they had willing runners and at half-time I said they wouldn't give in. The disappointing thing is we reminded them that we were 2-0 up against both Tottenham and Chelsea, the boys have got to learn that a game's never won and it's never lost."
The Development Squad were missing regular starters Dan Potts (Portsmouth), Blair Turgott (Colchester United) and Pelly Ruddock (Luton Town) who are all out on loan presently.
Kieran Sadlier, Dylan Tombides and Raphael Spiegel were also missing but despite the absentees Haycock refused to make excuses for his team's performance in their first league game in exactly four weeks.
"I don't want to make excuses. I've just said in the changing room that at the end of the day when you go out to play a game of football, whatever gap there's been, you make sure you're ready.
"We've trained just as hard as we normally do, probably even harder with some more physically demanding sessions. Some of the boys that have been out on loan and played regularly, most of them have featured in the Club's friendlies so I won't use that as an excuse.
"They know that they've underperformed tonight. You go through a team and normally you're looking for seven, eight, nine out of ten performances but there weren't many of them tonight and consequently we've got an under-par performance."
Haycock and his squad now turn their attention to Bristol City who they face in the Barclays Under-21 Premier League Cup on Monday.
The Robins beat Peterborough United to set-up a Round of 32 clash with the Hammers and Haycock is keen to get his side right for their taste of knock-out football.
"They've got to dust themselves down and come back with a little more bite about them and a little more authority about their game.
"We'll be travelling up Sunday for an overnight stay, preparing the DVD, we won't do too much on the pitch as we want to keep the energy levels high for the game.
"Most of the boys have played in the FA Youth Cup so I suppose this is the youth cup for Under-21s. All the teams have gone into it bar one or two and it's cup football which has to be done on the day and it's good that the Premier League have done that."