The person spoke to The Associated Press Monday on condition of anonymity because the Jaguars have not publicly announced details of the search.
Schwartz is interviewing Monday with coach Gus Bradley and others in Jacksonville. Schwartz is the third outside candidate to be interviewed, following Atlanta Falcons secondary coach Marquand Manuel and Miami Dolphins secondary coach Lou Anarumo. Manuel and Anarumo interviewed last week.
The Jaguars are looking to replace Bob Babich, who was fired Jan. 5.
The 49-year-old Schwartz went 29-51 as Detroit's head coach (2009-13). He was out of the league in 2015 after serving as Buffalo's defensive coordinator in 2014.
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