Ole Gunnar Solskjaer questioned the desire in his Manchester United players but insisted he will draw positives from the 3-3 draw against Sheffield United.
The Reds boss felt he could have substituted all 11 of his team at half-time after David De Gea kept them in the match when under siege at Bramall Lane.
It was Phil Jones who was replaced at the break, with the central defender making his first Premier League start of the season. Jones was at fault for John Fleck's opening goal.
"I was angry, disappointed, I had to wake them up," said Solskjaer. "You have to do something about it. I could have changed every player at half-time, apart from David (De Gea) as he kept us in it.
"It wasn't about tactics. It was about the desire first half, getting first to the ball, tackling, winning challenges. Sometimes tactics go out of the window.
"You have to earn the right to win a game and we didn't have any right to win the game after 70 minutes. We were nowhere near a Man United team.
"I don't doubt them wanting to win but sometimes young players don't know how to win challenges like this. Release the fear, play with belief and confidence."
Solskjaer thinks his young team will have learned some valuable lessons from Sunday's match.
The Reds were abysmal in the first half and fortunate to only be behind to Fleck's strike. Solskjaer admitted he was angry at half-time and his mood would not have improved when Lys Mousset doubled the hosts' lead early in the second half.
However, the Norwegian took some comfort from a sparkling seven-minute spell his side produced to turn the game on its head as goals from Brandon Williams, Mason Greenwood and Marcus Rashford had the Reds in front with 79 minutes on the clock.
Solskjaer was denied a sixth victory in the last seven matches by Oliver McBurnie's last-minute equaliser but he believes he and his players can take some positives from what had been a dire situation.
He said: "It was a very poor performance. I'm thinking back to Everton last season – that team gave up and this team didn't. So when we turned it around it's a great response to get from the boys,"
Blades boss Chris Wilder was left to rue the seven-minute spell that turned the match in the visitors' favour. However, he was also pleased with the way his team responded to that disappointment by striking back to earn a point.
Wilder said: "We just dropped off our energy levels. The old saying '2-0 is a dangerous scoreline' turned into 'oops, we're 3-2 down'.
"I would have been really disappointed had we not got anything from this game because for the majority of the time we were right up there in terms of the performance levels."
