As the NFL head-coaching carousel begins to spin, the Chicago Bears are believed to have requested permission to interview four NFL assistants to be the 16th head coach in franchise history.

Bears general manager Ryan Pace, who will make the final decision after collaboration with team president and CEO Ted Phillips and chairman George McCaskey, is not publicly acknowledging interest in any candidates for now.

Three of the four assistants who have been linked to the Bears can be interviewed this week since their teams earned first-round byes in the playoffs.

They are Philadelphia Eagles quarterbacks coach John DeFilippo, New England Patriots offensive coordinator Josh McDaniels and Minnesota Vikings offensive coordinator Pat Shurmur. The McDaniels and Shurmur interviews are scheduled for Friday.

The fourth candidate is Carolina Panthers defensive coordinator Steve Wilks. The Panthers face the Saints in New Orleans in a wild-card game Sunday.

Also, both the Bears and the Indianapolis Colts have put in requests to interview Kansas City Chiefs offensive coordinator Matt Nagy, according to Ian Rapoport of

Bears defensive coordinator Vic Fangio also is considered a possibility given the respect he has earned from his players and the impressive results he has achieved despite numerous injuries. But Pace declined to acknowledge his interest in Fangio.

"We're not going to get into who's a candidate and who's not," Pace said. "I have a lot of respect for Vic. He did a great job with our defense over the past three years. But we're not going to get into who's on that list or who's not right now."

DeFilippo and Wilks were the first names linked to the Bears late Monday morning. Several hours later at his 4 p.m. news conference, Pace said no interview requests had yet been made.

But that doesn't mean they haven't occurred since then.

Of those two, DeFilippo makes more sense given that the single greatest factor in the Bears' future success is the development of quarterback Mitch Trubisky.

DeFilippo has been an integral component in the meteoric rise of Eagles quarterback Carson Wentz, who in his second year was having an MVP season until a torn ACL ended it on Dec. 10.

McDaniels and Shurmur both are at the top of the list for multiple teams and both are considered quarterback gurus.

Shurmur gets kudos for the work he has done with quarterback Case Keenum, a mediocre-at-best journeyman in his first five NFL seasons who is having by far a career year with 22 touchdowns, 7 interceptions and a 98.3 passer rating.

All that despite the fact the Vikings lost their most dynamic runner, rookie Dalvin Cook, after four games.

McDaniels has been part of the Bill Belichick-Tom Brady coalition that has produced five Super Bowl wins for the Patriots. Aside from Brady, McDaniels also helped develop Jimmy Garoppolo and Jacoby Brissett.

In addition to the Bears, there are other teams looking to fill head-coaching vacancies: the Detroit Lions, New York Giants, Indianapolis Colts and Arizona Cardinals. The Oakland Raiders also are in the process of hiring a new head coach, but they appear to be fixated on Jon Gruden.

While McCaskey has painted the Bears' job as a plum assignment, there is little agreement with that evaluation outside Halas Hall.

"First of all," McCaskey said, "we're what the league refers to as a legacy franchise. We've been there from the start. Chicago's a great city. We have a roster that has a core of talent that needs to be developed. We've got a passionate fan base, and we will give the coach everything he needs to succeed."

ESPN rated the Bears' job the least attractive of the six teams currently with openings, behind, in order, the Lions, Raiders, Colts, Cardinals and the 3-13 Giants.

The Bears' job is more enticing than it was three years ago when John Fox took over because the roster is younger and the arrow is pointing up on several players who have yet to peak.

Asked if the job is more attractive than it was in 2015, McCaskey said: "I think this is a great job every day."

We'll soon see who agrees with him.