Terrion Arnold left Detroit's loss to Green Bay with a groin issue, and an MRI is planned for Monday to gauge severity. He played through a portion of the game but did not return, prompting a defensive shuffle that moved Amik Robertson to outside corner and Rock Ya-Sin to nickel. The Lions also offered only vague updates from coach Dan Campbell on Monday, keeping fantasy managers watching practice reps closely.

Arnold’s status is pivotal for Week 1 fantasy outlook. If MRI signals a longer absence, Robertson and Ya-Sin may absorb more snaps, raising short-term upside for Packers targets facing Detroit’s reshuffled secondary. Monitor Arnold’s MRI results and any Tuesday/Wednesday practice notes for clarity on corner rotations and potential Week 1 roles.