The young Gunners improved after half-time and pulled one back through Louis Zecevic John, but Reading held on for a 2-1 win.
Adam Birchall said Arsenal Under-18s paid the price for a poor first half and a failure to use the ball intelligently enough in their 2-1 defeat to Reading.
The young Gunners had been asked to follow up their 2-1 away win against West Ham by starting to build a more consistent run of results, but Birchall felt they gave themselves too much to do after a flat opening period.
Reading scored at the start of each half to take control of the scoreline, and although Louis Zecevic John pulled one back with an excellent finish in the 72nd minute, Arsenal could not find an equaliser.
“I’m disappointed with both the first-half performance and, of course, the result,” Birchall said.
“We challenged the players to build on the previous win and, as I’ve said in recent interviews, we want winning to become a habit. In the first half, we found it really difficult. We improved a lot in the second half, but ultimately it wasn’t enough.
“There were positives after the break, but overall we’re disappointed.”
The main issue, according to Birchall, was not effort or attitude, but the way Arsenal used their possession and built attacks.
“I think it came down to how we used the ball,” Birchall said. “In the first half, we were far too vertical. We played in straight lines and didn’t switch play across the back line enough, which meant we weren’t creating gaps in midfield.
“When we started to move the ball better in the second half, you could really see the difference. Our goal summed that up perfectly, it was probably the best team goal we’ve scored this season. The movement created more space, Reading found it harder to cover, and our midfielders were able to get on the ball more often, use the wide areas and create chances.
“We just weren’t able to take enough of those chances, but for me that was the key difference between the two halves.”
Birchall also felt the substitutes helped shift the momentum, giving Arsenal more energy and a clearer attacking threat, but he was still unhappy with what his side allowed Reading to do without the ball.
“The substitutes came on and made an impact, which is definitely a positive,” he said. “They have to learn how to influence games in those moments.
“Overall, our style of play and the number of chances we created in the second half were much better. We showed more energy and intensity with the ball, but we were still disappointed with what we conceded without it.
“Even so, the second-half performance was definitely an improvement.”
The u18s have one match remaining this season – a trip to face Crystal Palace on Saturday 16 May.