Nature of the test

It was a test to gauge their attitude. 

Yet, none were aware of it. Well, it wouldn't have been an attitude test had they known about it. There wouldn't be any meaning to it. 

Were they aware of it?

Hiro thought as he noticed the unchanged reaction of the veteran players. 

Now that he thought about it, before starting the game, Kenji Fujimoto was discussing something with the coach. 

"Kenji, don't intervene when they make mistakes. Let them handle their affairs. It doesn't matter whether they perform well or not. Just don't intervene."

These were Nanami's instructions to Kenji before the kickoff, which Kenji had quietly relayed to his fellow veterans.

That's why for the entirety of the game, despite their numerous blunders, they kept their mouths shut. As he recalled, everything began to fall in pieces.