Continuity mistake: Once Genzo is beaten, the ball is inside the goal towards the right. He walks away, nobody having touched anything, and the ball is towards the left. (00:11:00)
Continuity mistake: An indignant Genzo pushes Tsubasa away from him as he tries to aid him. Tsubasa lands with his back into the goal net, but Genzo pushed him away from the goal. (00:09:30)
Continuity mistake: When Tsubasa hits his header, he is far from the box; Genzo punches away with 4 of his teammates in front of him, but then in the aerial shot there are 13 (!) teammates on the field, about 6 close by, plus... Tsubasa himself. (00:07:55)
Other mistake: Tsubasa 'powers' in this episode get nerfed in the rest of the series; he is in elementary school and yet his shot flies literally miles off to land with precision in the arms of Wakabayashi. If he had this power and precision during a match, he'd be superhuman.
Plot hole: Once Wakabayashi wins his challenge against the Nankatsu senior students, he instantly is back at his huge mansion to collect Tsubasa's message. Tsubasa was standing just a few meters away watching The Challenge as it happened, and Genzo had no reason to run away (if anything he was supposed to supervise the team during training), nor he's shown doing that. He's just gone, no explanation. (00:15:20)
Other mistake: Genzo's challenge invites anyone to score shooting outside the penalty area...but we see that at least the rugby captain is standing inside the box. (00:12:20)
Continuity mistake: Ishizaki kicks the air to show that the injury is no biggie, and then clutches the injured ankle. Which was the right ankle, but his hand is on the left one. (00:04:50)
Other mistake: When Tsubasa kicks the soccer ball returning Wakabayashi's shot, the ball goes under the lorry and flies past several drive shafts. (00:21:50)
Blocked Off - S1-E6
Other mistake: When Tsubasa's dad spurs him before the second half telling him that he hates losers, there are trees in the background. He is in the stadium with everyone else. (00:19:35)