The Football Is My Best Friend - S1-E4
Continuity mistake: Sanae beats with a stick the naysayer; the stick has a flag wrapped around it the first time, then the flag is gone. (00:15:00)
No Easy Way - S1-E12
Continuity mistake: In the shot when the Meiwa team is begging Hyuga to play with them, the M of their jersey is black and not yellow. (00:13:50)
Continuity mistake: Morisaki in this episode is wearing the number 12 jersey, but he started the previous episode with the number 1. (00:08:35)
Continuity mistake: When Kojiro Hyuga lands after a wuxia-like leap over the goal, Genzo is suddenly not wearing his gloves. (00:14:55)
No Easy Way - S1-E12
Character mistake: In the first shot of the interior of the stadium, the banner says "We ♥ Nankatu", instead of Nankatsu. (00:03:40)
The Football Is My Best Friend - S1-E4
Continuity mistake: During his night training with high schoolers, Genzo is randomly shown wearing his gloves or not. (00:10:45)
No Easy Way - S1-E12
Factual error: Teppei Kisugi kicks the ball off advancing with the ball without passing to a teammate first. (00:19:45)
Other mistake: There are just 9 players (plus himself) when Genzo rallies the team after the goal. (00:15:10)
Audio problem: When Manabu shouts for the captain, his lips are not moving. (00:21:00)
Kick-Off for the Future - S1-E3
Other mistake: Urabe mentions that Nankatsu lost to Shutetsu 30 to 0 (which seems rather uncanny for a 40 minutes match), but the score mentioned in the first episode was 10 to 0. The more extravagant result ends up being the canon one.
Kick-Off for the Future - S1-E3
Other mistake: The kid who wants the soccer team to stop training is told off by Sanae, who points at the good efforts on the pitch. The animation of the team in training has noticeable errors, with a player that suddenly appears coming out of nowhere from behind the rightmost one, who is standing immobile in front of the goal and after a second disappears abruptly. (00:14:05)
Kick-Off for the Future - S1-E3
Continuity mistake: The girls in front and behind Manabu Okawa wear clothes different in colors literally in every shot. (00:10:30)
Other mistake: When Sanae tells to the team "Ishizaki is right!" and gives them a pep talk, she's practically a hobbit next to the others, and a couple players are on odd mounds as if it were a baseball field. On a soccer pitch you just can't have that sort of uneven ground. (00:19:00)
Other mistake: When Miss Ozora tells Roberto that he should have shown her The Letter from the beginning, Tsubasa is drawn looking in the wrong direction. (00:17:25)
Continuity mistake: When Genzo kicks the ball towards Tsubasa, the close-up shows the leg of someone wearing just thick white socks, while Genzo is wearing red pants that don't ride up that high. (00:21:40)
Continuity mistake: The inside of the truck Tsubasa and his mom ride in has stuff that change color/arrangement between shots. For instance, there's a beige box on top of the yellow and blue trunk next to Natsuko Ozora that is gone randomly in the aerial shots and when Yayoi is chasing them. (00:02:40)
Factual error: Tsubasa is daydreaming over a picture of Italy winning the 1982 World Cup. The uniform in the photo though has trunks and collars of the wrong color, a yellow that has never been part of any of Italy's sets. And even if it's certainly not a photorealistic cartoon, the features/hairstyles of the team depicted have nothing to do with the winning team; the winning team was not composed of gingers with big perms; the majority had black hair of medium to short length. (00:02:45)
Character mistake: In the map of South America, the nation of Chile is misspelled as "CHLIE." (00:18:05)
Other mistake: When Ishizaki is unwrapping his leg from the bandages, he's wearing the football boot he is NOT wearing before and afterwards. (00:15:10)
Continuity mistake: Coach Mikami's sunglasses are pitch black during most scenes, but in his reaction shot to the news of Roberto Hongo's international retirement they are tan. (00:11:35)