Steelers Rookie Named Best UDFA Signing

Following the end of the 2025 NFL Draft, the Pittsburgh Steelers took to the undrafted free agent pool to land some hidden gems. While taking just seven, fewer than most teams, the Steelers seem to have had good decision-making during the process.

Other than landing a college kicker who kicked in Acrisure Stadium to learn from Chris Boswell in Pitt's Ben Sauls, the Steelers also signed their third overall prospect out of Iowa in this process, signing safety Sebastian Castro following the selections of both Kaleb Johnson and Yahya Black during the draft. The Steelers also selected two players from the same college team when they selected linebacker Jack Sawyer and quarterback Will Howard of Ohio State.

When it comes to Castro, he has already begun to receive high praise for his abilities despite going undrafted.

The Athletic's Nick Baumgardner named Castro the Steelers best free agent signing in an article where he detailed every team's free agent signings.

"A three-year starting safety — and a playmaker — for Phil Parker’s always-tough Iowa defense, Castro doesn’t have elite athleticism but is an extremely smart defender, both in pass coverage (especially zone) and run support." Baumgardner wrote.

Despite taking a knock for athleticism, Castro's football IQ receives a highlight. It is entirely possible that Castro becomes an impact player for the team, as we saw an undrafted secondary player in Beanie Bishop get extended playing time during the previous season.

Castro was a two time All-Big Ten honoree, finishing as a second-team Big Ten player in 2023 and third team Big-Ten in 2024.

With 39 total tackles and three tackles for loss in his final collegiate season, Castro represents a work in progress, but an easy project due to his high level understanding of the game of football.