Facing 3rd and 5 at the Lions' 34-yard-line, Mitchell Trubisky connected with Anthony Miller for a 32-yard play that brought the Bears just two yards short of the end zone.
It appeared as though Miller may have bobbled the ball. Nonetheless, Matt Patricia didn't challenge the play. Given the stakes of how big this play was, and the fact that the Lions had three timeouts remaining, this was definitely a time Patricia should have challenged. There's no justifiable answer he can give as to why he didn't challenge this.
The Bears wound up scoring a touchdown on the drive.