I don’t think anything has changed. He said it himself, that this was what was in his heart all along. That he had been constantly running to forget about his fears and anxiety. It’s not about how he isn’t as good as everyone else. It’s not about him worrying about whether he’d be holding the team back. This is just him and himself.
It’s obvious Tsukamoto has huge anxiety and pressure regarding expectations and this isn’t something that can change, even if others tell you it’s okay. It’s all in your head and because this is the ultimate final stage for Seiseki as a team, it has finally caught up to him that this match is literally do or die and that pressure is way more immense than ever. The more they win and climb up the ladder, the more pressure Tsukamoto feels and he knows that he’s lost the chance to run away from it all, now that he’s built his reputation this far.
Don’t worry though. I think the coach has some words for him before he joins the match in probably the second half.
Sorry, I don't get why out cute little mc is suddenly panicking and feeling pressured now? What's changed?