"My freshman and sophomore years, we had lost in the semifinals, so finally winning it my junior year was really nice," he said. "... This year was very different. We only had two starting seniors, and I knew that going far [in the tournament] was going to be tough. We got there, but we did what we did."
Castillo looks back on his career at Juan Diego with pride. He scored 49 goals and notched 17 assists while becoming the most prolific offensive player in school history during his four-year career.
"He's always had immense soccer talent," Juan Diego coach Scott Platz said. "But when he first started as a freshman, he had some academic issues. He was a bit of a smarta--. He wasn't real mature yet. You fast-forward over the course of the next three years, and there have been a lot of changes.
"I think he took three AP classes this year, and he was an honor roll student. More importantly is he really found his identity as an individual. He's very conscientious, he's very sweet, he's just an awesome overall person. That's the greatest thing you hope for when you're working with young people."
Castillo said: "As a freshman, I didn't want to be shy. I wouldn't say I had an attitude, but I was very loud and very obnoxious. Come sophomore year, I changed. Juan Diego is a very prestigious school, and my parents don't come from a financial background where they can afford my schooling plus many other things. I wanted to make them proud, to show them how grateful I am. Academically was the way to do it. I would be the third member of my extended family to go to college, and I thought that was an important goal to set for myself other than playing. That's when I began to mature."
Another big step in Castillo's maturation was a torn meniscus in his knee that sidelined him for much of his sophomore season as well as nearly all of the following club soccer season. Castillo eventually retook the field for Juan Diego as a junior after an arduous rehab process. He helped the Soaring Eagle complete an 18-0 season to claim the school's first state soccer title.
"The coaches gave me confidence by starting me even though I still wasn't confident in my knee," Castillo said. "I think winning that championship was the best feeling I had because I knew at that point that nothing but my mindset was slowing me down anymore. Then achieving that, it really made me think about what I wanted coming into my senior year. Before that, I thought that what I wanted was to continue playing, but I realized that isn't what I wanted anymore."
Castillo gained a new interest in school while sidelined from soccer. A passion for reading and writing got him thinking about a future in the study of the humanities, so much so that he has decided to hang up his cleats — at a competitive level anyway — so he can focus on his studies at the University of Utah this fall.
"I want to keep playing for fun, but there's just a new experience that I want to be a part of, and that's my academics," Castillo said. "I just came back from the orientation at the university, and it was nice to know that this is going to be the next four years for me. Now instead of school and soccer, my life can be school and clubs, or whatever I want it to be."