Tom Pelissero

USA TODAY Sports

Amidst scrutiny of the Denver Broncos’ offensive issues and future at quarterback, an unresolved situation on the other side of the ball bears watching as GM John Elway, coach Gary Kubiak and company sort through the wreckage of a lost season.

Veteran defensive coordinator Wade Phillips’ contract is set to expire soon after this season ends, opening the possibility he could be coaching elsewhere in 2017, people with knowledge of the situation told USA TODAY Sports.

Phillips agreed to join the Broncos on a two-year contract in late January 2015. The sides discussed an extension after Phillips’ top-ranked defense drove Denver’s Super Bowl title run last season, but they never agreed to terms, said the people, who spoke on condition of anonymity because contract matters were to remain private.

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In his 46th season of coaching and showing no signs of wanting to retire as his 70th birthday approaches, Phillips is set to become a free agent a few weeks after Sunday’s finale against the Oakland Raiders. So the clock is ticking for Denver to extend his contract or risk losing one of the league’s respected defensive minds.

And while the Broncos' goal is continuity, they feel they have a tremendous staff on defense beyond Phillips, led by line coach Bill Kollar, linebackers coaches Reggie Herring and Fred Pagac and defensive backs coach Joe Woods.

Phillips has a history with Kubiak, whom he previously coordinated under with the Houston Texans from 2011 to ’13 before spending 2014 out of football. Few potential suitors would offer personnel rivaling Von Miller, Aqib Talib, Chris Harris Jr., et al. The most logical outcome is Phillips gets a new deal and stays. But unless and until a deal is done, nothing is certain.

The Associated Press named Phillips the NFL assistant coach of the year last season, when his defense carried a Broncos team that went through multiple quarterback changes before shutting down Carolina Panthers star Cam Newton in a Super Bowl 50 victory.

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The Broncos are 8-7 this season and were eliminated from playoff contention last weekend. The loss of defensive lineman Malik Jackson to free agency and injuries to Vance Walker and others have contributed to Denver’s struggles stopping the run. But Phillips’ defense once again ranks among the NFL leaders in several key categories, including yards per play (first), yards per pass play (first), sacks per pass play (third) and third-down efficiency (seventh).

Other questions facing the team’s brain trust include their plan under center, where the Broncos could look outside the building to find competition for incumbent quarterback Trevor Siemian and first-round draft pick Paxton Lynch next season.

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