What happened: Seattle is adding Arnold after a preseason tryout. He visited multiple teams before choosing the Seahawks.
Why it matters: The short commitment gives Seattle the 2026 season to evaluate Arnold in its secondary. Detroit released him in June with two years left on his rookie contract.
By the numbers: Arnold recorded 91 tackles, 18 passes defensed and one interception across 24 games, including 22 starts, for Detroit.
What to watch: Arnold's remaining preseason work will clarify his place in Seattle's cornerback rotation.