On Cards' search for defensive coordinator

Keith Butler, the Arizona Cardinals' logical but undeclared top choice to become defensive coordinator, appears likely to remain with the Pittsburgh Steelers.

The Cardinals requested permission to interview Butler, but the Steelers denied their request for the second time in three seasons, Kent Somers of the Arizona Republic reported. That comes as no surprise, diminishing the degree to which the news qualifies as a setback. Landing Butler would have been a best-case scenario based on his experience and the fit with the Cardinals' staff.

Cardinals coach Ken Whisenhunt, who worked with Butler in Cleveland and Pittsburgh, could still land a coordinator with roots in the Steelers' organization. ESPN's Adam Schefter and others are listing Steelers secondary coach Ray Horton as the favorite. Hiring Horton would require more projecting because the former NFL cornerback and longtime secondary coach has no experience as an NFL coordinator and Whisenhunt, as an offensive-minded coach, would not be in position to take over defensive play-calling in a pinch.

The Dallas Cowboys also reportedly have interest in Horton, but as a secondary coach.