Detroit shocked Arrowhead, edging the Chiefs 21–20. Jared Goff threw for 253 yards, rookie Brian Branch returned a Mahomes interception 50 yards for a pick‑6, and David Montgomery punched in the go-ahead TD late.
The Lions’ defense clamped down, holding KC 0-for-7 on third downs in the second half. Arrowhead was stunned — Detroit came, saw, and roared.