The Arizona Wildcats rose to prominence in the 1990s by playing a swarming flex defense.

Today, they returned - in spirit, at least - to their football roots.

Call it the Desert Stack.

The UA has hired West Virginia defensive coordinator Jeff Casteel and two of his Mountaineers colleagues to implement the same 3-3-5 "stack" defense that helped win this year's Orange Bowl. David Lockwood will coach the Wildcats' cornerbacks, while Bill Kirelawich will handle the defensive ends. Casteel will call the plays and coach linebackers. 

A fourth assistant, Spencer Leftwich, was introduced as the UA's tight ends coach. He spent one season at Pitt, where he worked alongside three coaches - Tony Gibson, Tony Dews and Calvin Magee - currently on the Wildcats' staff.

The Star reported all four hires on Tuesday, the 50th day of Arizona's search for a defensive coordinator. The UA confirmed the moves with a news release this afternoon.

"We are very excited to have Jeff, David, Bill and Spencer, and their families, join our family here at the University of Arizona," Rodriguez said. "They are not only great coaches, but great people who bring a lot of quality experience and knowledge to our staff."

Arizona's new defense marks a departure from former coach Mike Stoops' 4-3, NFL-inspired system. Casteel's scheme features three down linemen, three linebackers, three safeties and two cornerbacks. The linebackers position themselves behind the defensive linemen, allowing the safeties to freelance depending on how aggressive the defense wants to be. Coordinators can put at least eight defenders in the "box" on any given play.

The Rodriguez-Casteel reunion fits, in part because both coaches were instrumental in popularizing it at WVU. Upon arriving in Morgantown, W. Va., Rodriguez instructed his defensive staff - which included Casteel - to find a defense that would allow the Mountaineers to play to their strengths: linebackers and speedy safeties.

"We thought we'd be able to get a niche in recruiting where we weren't able to go recruit 3-technique (players). We thought it might be easier to get ‘tweener' guys," Casteel told reporters at the Orange Bowl last week. "Along with Rich bringing in the spread (offense), and trying to get a niche offensively, and it's kind of grown from that. It's been good to us over the last 8, 9, 10 years. We've been fairly consistent, and it's been good for us."

Casteel brings two WVU lifers with him to Tucson. Kirelawich spent the last 32 seasons at West Virginia, coaching outside linebackers and the defensive line. He started as a part-time assistant in 1979, and was promoted to a full-time job a year later.

Lockwood, a former WVU defensive back, spent two stints coaching at his alma mater. Before that, he coached DBs at Kentucky (2007), Minnesota (2002-06), Notre Dame (2000) and Memphis (1999). He has also coached at Delaware and James Madison.

Leftwich comes from Pitt, where he spent the 2011 season as offensive line coach. Before that, he coached the position at Tulsa (2003-06, 2010), North Texas (1994-2002, 2007-09), New Mexico State (1992-93) and Stephen F. Austin (1989-91). Leftwich, a native of Gainesville, Texas, will recruit the Lone Star State for the Wildcats.

The sports editor of the Arizona Daily Star.