Hernandez first showed up in Captain Tsubasa back in 1981, specifically in chapter 86 ("Greeting From an Old Enemy"). He's Italy's goalkeeper, wearing the #1 jersey.
The guy's got a real ego about being Italy's "Perfect Keeper"—and honestly, he lives up to that nickname pretty well. He takes his role seriously and wants to prove himself every time he's on the field. What's interesting is how he handles losses: when Japan beats him, he's genuinely gracious about it, willing to acknowledge that Tsubasa and the team outplayed him. But that sportsmanship doesn't extend to his matches against other teams—he's notably less cool about losing to them. So his respect seems reserved specifically for Japan, which fans often note as a quirk of his character.
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