The Detroit Lions are on a bye week, and they can keep smiling going into it because they're coming off a 45-21 win over the Arizona Cardinals. The Cardinals are the kind of team the Lions are expected to beat, but there are no easy wins in the NFL, so at least head coach Dan Campbell and company can breathe a sigh of relief.

Throughout the season, when it comes to the Lions' problems, and there have been many with their 3-2 record, the biggest has been on defense. Last season, the offense didn't seem to mesh following offensive coordinator Ben Johnson's departure to the Chicago Bears. But this season, defensive coordinator Kelvin Sheppard has really had to answer for a weak showing on defense.

Detroit Lions defensive coordinator lands on NFL analyst's hot seat list

In a piece published on Thursday, Bill Barnwell of ESPN names 15 coaches and players on the "hot seat" heading into Week 6 games. For the Lions, he points to Sheppard.

"Sheppard made it through Year 1, but unless things improve, it's tough to see him surviving through the end of a second season in the defensive role," he notes in the piece.

So, if the Lions keep losing and the defense is to blame, there's a case to be made that head coach Dan Campbell and general manager Brad Holmes will have to rethink the defensive coordinator position. Of course, the buck stops at the top, and if the losses pile up, people will start looking at Campbell and Holmes, too. But for now, Barnwell makes the case that Sheppard is in the "hot seat," and the pressure is on for him to turn things around as much as possible this season.

"Sheppard will obviously hope to get more help," Barnwell notes, "but the Lions can't compete for a title if their defense continues to blow leads in the fourth quarter."

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