Louisville has its fourth defensive coordinator in 14 months.
Coach Steve Kragthorpe promoted Brent Guy to the position on Friday, a week after Guy joined the staff as linebackers coach.
Guy replaces Bill Miller, who briefly held the job for a few weeks before taking a job at Kansas.
Guy joined the Cardinals after spending four seasons as coach at Utah State. Before that he was defensive coordinator at Arizona State for four years. He'll be in charge of helping shore up a defensive unit that must fill massive holes along the line.
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Arkansas: Former Michigan State and Louisville coach John L. Smith has been hired as special teams coordinator.
The Razorbacks said Smith also would help with the defense. Smith was the Spartans' coach for four years before being fired after the 2006 season. He coached Louisville from 1998-2002.
Smith was the coach at Utah State during the 1990s and had Arkansas Coach Bobby Petrino on his staff.
Mississippi: Terry Price, first cousin to recently departed line coach Tracy Rocker, is the Rebels' new defensive line coach. Rocker left to take the same position at Auburn, where Price had been defensive ends coach for the last 10 years.