Andrea Pirlo referred to his squad as 'young' and 'naive' after they were held to a 1-1 draw against promoted Crotone on Saturday.
Pirlo believes players such as Federico Chiesa, who signed from Fiorentina during the recent transfer window, need to gain experience in order to mature after he was given a straight red card for a studs-up challenge on Luca Cigarini.
Pirlo claims the international break has prevented such growth within the squad and admits the absence of Cristiano Ronaldo, Alex Sandro, Aaron Ramsey and Paulo Dybala played a role in their defeat.
'Unfortunately, we went down to 10 men in the last two games because of our errors, but we are a young team that needs to work and there hasn't been much time for that with so many internationals,' he told DAZN.
'Young players need to gain experience by playing in matches and it can happen that they make naive errors as part of the learning process.
'We built a team with quality, but it is still a work in progress and needs time. The lads will learn through mistakes, unfortunately that also means taking a few risks in the early matches of the season.
'We made a few mistakes in the timing of the press, but as I said, these things happen when we're still getting the machine oiled. We only really spent half-an-hour on this tactical movement in training yesterday, so it will improve.'
In addition, Pirlo was missing Cristiano Ronaldo and Weston McKennie after the pair tested positive for coronavirus on Tuesday.
While Alex Sandro, Aaron Ramsey and Paulo Dybala remained unavailable for the Juve boss as they continue to recover from injury.
The absence of such players saw Pirlo look to those less experienced players to set up.
The manager did, however, admit they had 'very little time' to practice their new formation ahead of their game with Crotone.
He said: 'We had very little time to practice, we had a first training session all together yesterday. We have players like Chiesa and Morata who attack the space, so the idea was to find passes between the lines, and that is how the goal was created.'
Crotone boss, Giovanni Stroppa, was proud of his sides performance but claims his side should have taken advantage of Chiesa's red card.
'We've conceded a few goals with naive errors, but I still believe we are on the right track,' he said after the game.
'We could've made more of the extra man and been sharper in the final third, taking them on one-on-one, but we still did well with 11 against 11 and 11 against 10.
'This is not the best Juve team, but we saw they still had remarkable talents to come off the bench and bring new elements to the side, so we can be proud of this result.'