The Steelers have a potential undrafted gem on their roster.
All the talk this offseason has been about the quarterback position in Pittsburgh and when Aaron Rodgers will decide to join the team. And while that’s understandable, considering the importance of having a good quarterback, there is one player on the Steelers’ roster that flew completely under the radar during draft season, which led to the Steelers being able to sign him as an undrafted free agent.
Former Iowa safety Sebastian Castro is a fascinating player. The former Hawkeyes safety was one of the more reliable and versatile defensive backs in the country in 2023, but did take a step back in 2024. Regardless, he has shown the ability to play all over the defensive backfield, and even held current Steelers wide receiver Roman Wilson to just one catch back in the 2023 season when he went man-to-man with him.
Iowa DB Sebastian Castro said that the Michigan game in 2023 was the best of his career.
Here were some of his man coverage snaps versus Roman Wilson, Steelers 3rd round pick, who finished with just 1 catch on the day. pic.twitter.com/dvJCzs1UmR
— Derrick (@Steelers_DB) February 27, 2025
In that terrific 2023 season, though, Castro had three interceptions and earned an astounding 91.2 grade from PFF en route to becoming a Third-Team All-American in 2023. And while he didn’t quite replicate that play in 2024, he was a Third-Team All-Big Ten selection last season.
Castro lines up all over the field. He plays in the slot, he plays deep, he plays in the box – whatever you want him to do, he can do it. I don’t really do comps for players because no two guys are exactly the same, but his absolute ceiling would be Tyrann Mathieu – a guy who can make splash plays with interceptions, but will play that thumper role in run support and have a primary role as a box safety.
New Steelers duo at work.
Yahya Black anchoring down and collecting a double team to keep Sebastian Castro clean to make the run stop. pic.twitter.com/yLWSNUUdZF
— Derrick (@Steelers_DB) April 28, 2025
Iowa CB Sebastian Castro with an outstanding 1/4 flat zone drop to wall #2 off and then undercut the sail route for a leaping interception near the sideline. pic.twitter.com/H7Aln6njZJ
— Derrick (@Steelers_DB) November 19, 2024
With the Steelers somewhat thin at safety behind Minkah Fitzpatrick and DeShon Elliott, I’ll plant my flag and say Castro makes the roster in 2025, and is an eventual starter down the road. Minkah Fitzpatrick isn’t getting younger, and this is the final year of Elliott’s deal. They did bring in Juan Thornhill as a free agent signing from the Cleveland Browns, and Miles Killebrew will take a roster spot for special teams – I think Castro beats Thornhill out for a roster spot.
Castro is one of the players I’m most excited to see up close during mini-camp and training camp, as well as preseason play, to see if he can indeed crack that final 53-man roster. With his versatility, he can help the Steelers both on the back end, as well as in the slot. If he can, I won’t be shocked if he is competing for legitimate snaps come 2026.