John Fox and Jeff Saturday break down Andy Reid's efforts to find a new defensive coordinator after the firing of Bob Sutton. (1:34)

Former St. Louis Rams and New York Giants head coach Steve Spagnuolo has emerged as the favorite to replace Bob Sutton as the Chiefs' defensive coordinator, sources told ESPN's Adam Schefter.

Spagnuolo, 59, and Andy Reid worked together in Philadelphia, share the same agent and have a mutual respect for each other's work.

Spagnuolo was with the Eagles from 1999 to 2006 as a defensive assistant, defensive backs coach and linebackers coach before becoming the Giants' defensive coordinator in 2007 and 2008.

He became the Rams' head coach in 2009 but was fired after the 2011 season, finishing with a 10-38 record.

He then became the Saints' defensive coordinator in 2012 and was on Baltimore Ravens staffs in 2013 and '14 before returning to the Giants as defensive coordinator from 2015 through '17. He was the Giants' interim coach in 2017 after Ben McAdoo was fired and went 1-3 in the role.

With Spagnuolo as the defensive coordinator, the Giants finished in the top 10 defensively three times (2007, '08 and '16).

The Chiefs fired Sutton on Tuesday after his defense was unable to come up with pivotal stops against Tom Brady and the New England Patriots in the AFC Championship Game. He had been the Chiefs' defensive coordinator since Reid became the team's head coach in 2013.

The Chiefs finished 31st in total defense this season, in contrast to the offense, which finished No. 1 overall in the NFL.

The Chiefs scored at least 28 points in each of their five losses this season, including games in which they scored 51 and 40 points.