That's the good news for a struggling Detroit team.
Coach Jim Caldwell updated the status of Stafford and Mathis on Monday, with the Lions set to travel to London for Sunday's game against the Kansas City Chiefs. Detroit lost 28-19 to Minnesota last weekend, and Stafford was knocked around by a pass rush the Lions couldn't handle.
Stafford threw for 256 yards and two touchdowns, but he was sacked seven times.
Mathis went through the concussion protocol, but Caldwell said it was determined he did not have a concussion.
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