Matt Gill praised his Under-23s character and resilience as they fought from two goals down to beat Reading 3-2 at Colney.
City trailed by two goals after half-an-hour but roared back and managed to win for their first points of the Premier League 2 season.
"Obviously we didn't start the game great, but to win the game 3-2 shows real resilience from such a young group, so I'm delighted," said Gill.
"We started the game horrifically and we were in the mode of: 'We're going to have a nice game of football.'
"It was a lovely day, the pitch was great, some of the lads have just come up from Under-18s football and I think they had the wrong attitude early on.
"They need to recognise quickly that it's proper football and they need to learn the right to play.
"We need to play to our strengths. It was a good learning experience today on how to start a game.
"To stick with it and keep going at 2-0 down showed superb character and resilience."
Gill reserved a special mention for winger Simon Power who scored City's first on the day.
"He deserves a massive mention. He kept running in-behind and worked really hard. He was terrific today.
"He was involved when their man got sent off and really stuck at it. That's the mentality we need.
"To score in the first-half was vital for us. He's capable of that, to score out of nothing."