Chiefs to start Juan Thornhill over Daniel Sorensen at safety in hopes of reigniting defense

The Chiefs defense is making a big change at a key time.

Sources say safety Juan Thornhill is expected to start at safety moving forward, with veteran incumbent Daniel Sorensen headed to a reserve role.

The highly anticipated move comes on the heels of a brutal loss to the Bills that saw Sorensen struggle mightily during important moments. Sorensen gave up a 61-yard pass to Stefon Diggs to make way for a Buffalo field goal, then allowed a 53-yard touchdown pass to Dawson Knox, with the Bills tight end slipping past the last line of defense.

With the Chiefs defense currently 31st in yards and 32nd in points allowed, Thornhill won't cure all. But the former second rounder, who burst onto the scene as a rookie to look like a budding star, will help.

Thornhill tweeted after last week's game: "Never said it would be easy, but we will get to where we want to be." The soon-to-be 26-year-old now enters a bigger role.

As a rookie, Thornhill appeared on his way to stardom. He started in the opener, was named to various all-rookie teams and always impressed. Then, he tore his ACL in late December of 2019 and battled knee pain throughout 2020. Not quite himself, he was suddenly a part-time starter.

This year, as he's gained confidence, Thornhill has put himself in position to start. Sorensen had been considered the security blanket, but it hasn't been that way. Per Pro Football Reference, he has nine missed tackles -- a whopping 20.5% of his opportunities -- and is giving up a 153.8 passer rating when targeted.

Pro Football Focus has graded Sorensen last among K.C. defenders this year and 83rd among 85 safeties in the NFL with 100-plus snaps. By contrast, Thornhill is fourth among K.C. defenders and 29th among 85 safeties with more than 100 snaps.

Defensive coordinator Steve Spagnuolo, while meeting with reporters this week, was asked about the play of Sorensen, which has drawn increased criticism in recent weeks.

"First of all, it's not about one guy," said Spagnuolo, in his third season as DC for Kansas City. "To focus on one person, I don't think is fair. Did Dan struggle a bit last week? Yeah. … We take a guy who has a starting position, we think a guy has been doing a good job. Sometimes when you have plays that to the eye of everybody in there look worse than other ones, nobody sees the plays that he's making when you're covering somebody and they don't throw it there. I think Dan's had a lot of good snaps for us."

In the next breath, Spags declined to disclose if there would be changes and what packages will be on the field. In part, no doubt, because of the change that was coming.

"We'll work through who is playing where, what we're doing package-wise," Spagnuolo said earlier this week. "I won't go deep into that because we're getting ready to play a team. I'm not going to tell everybody what we're doing."

Later, he added, "We're always trying to put people in the right spots."

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