Late Bloomer with a High Motor: Sebastian Castro Fights for a Spot in Pittsburgh
by Bo Marchionte
@bomarchionte | College2Pro.com
Published June 3, 2025, 1:37 PM
Pittsburgh, PA – Going undrafted in the NFL is no small mountain to climb. For Sebastian Castro, it’s a climb he’s all too familiar with. The former Iowa Hawkeye safety has always taken the road less traveled. Now, with the Pittsburgh Steelers giving him a chance, he’s working every day to prove he belongs.
“I wasn’t always a star player,” Castro admitted. “Not from the get-go. Not when I was, what, eight years old? I thought I was probably an O-lineman, just a chubby kid growing up.”
The self-described “late bloomer” eventually slimmed down and sprouted up, but his journey has always been about effort, not flash. He’s not the kind of athlete who turns heads with a 4.3 forty. He’ll be the first to admit that. But in a city that reveres grit, Castro’s high football IQ and relentless motor may be just what gets him in the door and keeps him there.
“The reason I’m in this position is because I’m a player with a high football IQ,” Castro said. “I know how to position myself well, and I just have a high motor. One of the reasons I’m here is I’ve been working hard my whole life that’s just who I am.”
That mentality fits the DNA of a Steelers defense built on toughness and tenacity. Whether he’s competing for a role on special teams or rotating in the secondary, Castro understands that effort and attitude can tip the scales.
“It helps a lot in that role,” he said. “Either special teams or on the field if you’re starting, running around, just trying to set a tone, having a certain attitude. That’s what I’ve been my whole life.”
Castro’s game is as much about the neck-up as it is about what happens on the field. He takes pride in his preparation, crediting his mental approach and time in the film room as keys to his development.
“I spent a lot of time in that film room,” he said. “If anyone’s ever considering stuff like IQ, it comes from somewhere. It comes from preparation. That confidence it comes from understanding the game.”
At Iowa, Castro earned the trust of defensive coordinator Phil Parker a notoriously detail-oriented coach who rarely grants liberties in his defense. But Castro’s deep understanding of the scheme allowed him rare autonomy.
“As you got older, Coach (Phil) Parker would give the older guys more freedom,” Castro said. “He would trust you to go outside the scheme, take a couple chances. I tried that this past year didn’t always work out but it all comes with discipline and just learning from mistakes.”
The Pittsburgh secondary has a legacy that looms large, especially at safety. It’s a tradition Castro embraces. Growing up, he watched Hall of Fame talents to help shape his on football resume.
“I grew up watching legends,” he said. “Guys like Troy Polamalu that’s why I play how I play. Because of guys like him, Ed Reed… all of those players.”
Though he doesn’t boast the same athletic gifts as those icons, Castro’s approach mirrors their mindset. His style is about positioning, anticipation, and controlled aggression.
“I’ve always been a downhill player,” he said. “Knowing angles, knowing how to tackle, reading the quarterback that’s what I pride myself on.”
Scheme fit matters for a player like Castro, and he’s self-aware enough to know where his game can flourish.
“You can find yourself in a scheme where nickel’s more freelancing, not playing man all day, chasing guys,” he explained. “I’m not built to chase 4.2, 4.3 guys the whole day. That’s not my game. But I know how to put myself in the right place.”
As training camp unfolds on the South Side of Pittsburgh, Castro remains locked in battling to carve out a role on one of the NFL’s most historically rugged defenses. Every day is an audition. Every rep counts. And for a guy who’s never had anything handed to him, that’s nothing new.
“I’ve been working hard my whole life,” Castro repeated. “That’s just who I am.”
Photo Credit Frank Hyatt/College2Pro.com
