The Premier League club have struggled to field a fully fit team all season.
Despite rotating his team and signing a lot of players, Postecoglou has been left relying on kids in some games.
Speaking this week to reporters, he stated: “With regards to the first part of your question, it’s a combination of both. You’re always assessing why it’s happening, that’s only logical. In the early part of year there were things repeatedly happening, guys coming back from injury and getting re-injured and that kind of cost us. So we’ve worked hard to try and better that process but recently it’s been accumulation and the toll of fixturing.
“We’ve been hit the hardest but it is becoming more prevalent. If you look at the teams in Europe, even last year, Newcastle really suffered, and Villa to a certain extent this year. You really need a strong squad of players and keep them healthy to cope with playing in Europe if you do well in the cup competitions like we have because it’s not manageable when you’ve got three games a week for the length of time we have.
“Some of it is because we've done well in the Carabao Cup and that’s added extra games to our fixturing, and in Europe this year two extra games… so all these things are taking its toll. People may look at us and think it’s a unique case. It's a very extreme case for sure but I don’t think it will be as uncommon as people think as we move along. There’s some warning signs there for others but we’re paying the toll right now.”