Character mistake: Roberto says that Misugi already "peaked as a player" as opposed to Tsubasa who can improve. Since he does not know of Misugi's heart condition, the notion that a football player reached already his full potential when he is barely 11 years old is nonsense.
Other mistake: Misaki dispossesses Akira Ichinose with an aerial tackle (which would be illegal anyway, since he's by every mean doing a flying kick at an opponent), but for that to happen the way it is shown, the player already must have lost control of the ball, since Misaki 's foot is hooking a ball situated behind the back leg of Ichinose. It's not what it is supposed (and described) to happen. (00:15:20)
Continuity mistake: At halftime, the Musashi team members are toweling the sweat away. There are white, yellow, teal towels, but when one of them says that they are winning thanks to Misugi, he has a lavender towel, and the towels are all gone altogether when they answer "Yes" at the end. (00:03:45)
Continuity mistake: Stripes and bangs of one of Misugi's female supporters in the crowd change again like they did in the previous episode, this time to a third different pattern. In this very same episode they are shown in recycled shots from their first appearance (thin red stripes on the top), too. (00:04:45 - 00:07:40)
Continuity mistake: Misugi manages to block the "Golden Combi" intercepting Misaki's pass to Tsubasa. His cheerleaders voice their appreciation; next to a girl that wears a "JUN" T-shirt, there's her friend with a striped red and white tee. Too bad that it's entirely different stripes than before, from being of the same size to very thick whites and thin reds. (00:18:25)
Character mistake: The characters keep referring to this match as Jun Misugi's last, hoping he'll win it, but Meiwa is an opponent just as fierce as Nankatsu, so even if Misugi beat Tsubasa, he would need to play still one more match. It's Misugi's last only if he loses (as in fact happens, but they can't know that).
Factual error: Ken Wakashimazu, the reserve keeper, just announces a substitution, himself, from the crowd (not even the bench!), his presence unbeknownst to the coach and everyone else in attendance. For those not familiar with the rules of soccer (or ANY sport!), that's really not how it works in an official match. (00:13:30)