Trestman was not a known candidate for any other job. His rather curious hiring should not affect the Cardinals in any way.
A quick look at the known candidates for the Cardinals, Eagles and Jaguars:
Arizona: Offensive coordinators Darell Bevell (Seattle), Jay Gruden (Cincinnati) and Todd Haley (Pittsburgh) have reportedly interviewed or will interview. Cardinals defensive coordinator Ray Horton has already interviewed and remains on staff. Andy Reid and Mike McCoy were candidates before taking jobs elsewhere.
Eagles: The Eagles have interviewed and/or pursued Seahawks defensive coordinator Gus Bradley (Seattle), former Cardinals head coach Ken Whisenhunt, Gruden, McCoy, Atlanta Falcons defensive coordinator Mike Nolan, Falcons special-teams coordinator Mike Armstrong, Falcons offensive coordinator Dirk Koetter, former Baltimore Ravens coach Brian Billick, Notre Dame coach Brian Kelly, Oregon coach Chip Kelly, Penn State coach Bill O'Brien, former Chicago Bears coach Lovie Smith, and then-Syracuse coach Doug Marrone. Did I miss anyone? Phil Sheridan of the Philadelphia Inquirer joked that the Eagles have interviewed "every living male with a visor" to this point.
Jaguars: Bradley headed from his Eagles interview to meet with the Jaguars on Wednesday. Bevell and St. Louis Rams offensive coordinator Brian Schottenheimer also interviewed. Schottenheimer was a finalist for the job one year ago, but the Jaguars hired Mike Mularkey. Jaguars defensive coordinator Mel Tucker interviewed. San Francisco offensive coordinator Greg Roman would be a logical candidate for the job given his success with the 49ers and close ties to new Jaguars general manager David Caldwell, Roman's former college teammate and roommate. The Jaguars were not yet conducting their coaching search when Roman was available for interviews during the window provided before divisional-round games. He remains off-limits during Championship Game week. Armstrong, the Falcons' special-teams coach, has also been mentioned as a candidate. AFC South blogger Paul Kuharsky sizes up the field.
The chart is an expanded version of previous ones I've produced, designed to show which openings might be most appealing from candidates' perspective. I would order them Philadelphia, Arizona and Jacksonville based on a range of factors, including quarterbacks and ownership.