The Steelers claimed safety Sebastian Castro off waivers after he was released by the Tampa Bay Buccaneers.
Castro began the 2025 season on the Steelers practice squad, but was signed to the Buccaneers 53-man roster on Sept. 30, where he appeared in one game.
Castro originally signed with the Steelers as an undrafted free agent following the 2025 NFL Draft out of Iowa.
Castro appeared in 53 games for the Hawkeyes, starting 32. He finished his career with 163 tackles, including 113 solo tackles. He had 14 tackles for a loss, 18 passes defensed, five forced fumbles, four interceptions and two sacks.
To make room for Castro on the 53-man roster, the team released safety Juan Thornhill. Thornhill was signed as an unrestricted free agent during the offseason.
In seven seasons, Thornhill has appeared in 96 games, starting 75. He has 370 tackles, 252 of them solo stops, eight interceptions, and 25 passes defensed. He appeared in nine games in 2025, starting one, and has 35 tackles, 20 of them solo stops, and one pass defensed.
