The NFL is a tough business.

Ex-Denver Broncos head coach John Fox went 46-18 in four seasons with the team, making the postseason every year, including one Super Bowl appearance. None of it was enough to save his job, however, as the Broncos have loftier goals than just hanging around the playoffs. General manager John Elway and Fox mutually agreed to part ways yesterday, making the coach a free agent.

With five open head coaching positions across the NFL, Fox is already drumming up interest in his services.

"John Fox will soon interview for the Chicago Bears' head-coaching vacancy, but he is not locked in for the job, according to sources," ESPN's Chris Mortensen wrote.

The Bears have empowered new general manager Ryan Pace with final say over the coaching search. It is unclear if he thinks Fox is up to the task.

"Sources say the 37-year-old GM will want to be certain his choice has the sustained energy to embrace the challenge of leading a team that can overcome a competitive NFC North division and win a Super Bowl," Mortensen wrote.

Fox led the Carolina Panthers and Broncos to Super Bowls, losing both times. He has a career playoff record of 8-6.

The Bears have also been linked to Mike Shanahan, Seattle Seahawks defensive coordinator Dan Quinn, Arizona Cardinals defensive coordinator Todd Bowles and Broncos offensive coordinator Adam Gase. Working in Fox's favor, however, is a small level of familiarity with Pace. Pace worked with the New Orleans Saints for 13 years while Fox coached the Panthers in the NFC South. Saints coach Sean Payton is a mutual friend of both men.

We'll keep you updated as Chicago's head-coaching search continues.