Per ESPN's Adam Schefter, Joseph is facing "increasingly longer odds" to be brought back by the Broncos in 2018.
Per Alex Marvez of the Sporting News, Joseph had been operating this week with the expectation he would return to the Broncos next season, but general manager John Elway had not made a final decision.
The Broncos hired Joseph in January to replace Gary Kubiak, who stepped down after last season for health and family reasons.
Prior to joining the Broncos, Joseph served as defensive coordinator of the Miami Dolphins in 2016. He also worked as a defensive backs coach for the Houston Texans, Cincinnati Bengals and San Francisco 49ers.
Denver sits in last place in the AFC West with a 5-10 record. The Broncos started this season 3-1 before losing eight straight games to miss the playoffs for the second straight year after winning Super Bowl 50.