After a seven-year absence, the firm of Kiffin & Marinelli is back in business.

During their decade together in Tampa, defensive coordinator Monte Kiffin and defensive line coach Rod Marinelli forged an impressive résumé, highlighted by the 2002 championship season. Now, they're back together in Big D, where the Cowboys are hoping their version of the Cover 2 can work effectively deep in the heart of Texas.

Some say the NFL is a young man's game, but that maxim will be tested this fall. Kiffin is 73 and Marinelli turns 64 shortly before the Cowboys open training camp.

Since they parted company, Marinelli and Kiffin have found mixed success.

Marinelli left the Bucs in 2006 to become the head coach in Detroit, where he won 10 games in three years, capped by an 0-16 slate that left the Lions with little choice but to fire him. When Bears head coach Lovie Smith reached out in 2009, Marinelli was eager to rejoin a former Bucs assistant and close friend.

After one year as defensive line coach, Marinelli assumed defensive coordinator responsibilities in Chicago and the Bears led the NFL with 44 takeaways last season. After Smith was dismissed, Marinelli had an opportunity to remain on the staff of new coach Marc Trestman, but he declined, citing his loyalty to Smith.

Loyalty is a key word in Marinelli's vocabulary. He embraces old-school values, choosing to take on a lesser role in Dallas (defensive line), rather than a coordinator job in Chicago.

The chance to reunite with Kiffin was also alluring.

With the Bucs off to a 9-3 start in 2008, Kiffin told Tampa Bay players he was leaving after the season to join his son, Lane, at Tennessee.

That announcement triggered a four-game slide that cost coach Jon Gruden his job as Tampa Bay failed to make the playoffs. The relationship between Kiffin and Gruden hasn't been the same since that epic collapse, and Kiffin's defense wasn't particularly stout once he followed Lane to Tennessee and then Southern California.

Now, he's back where he belongs, breaking down NFL attacks and looking for the right personnel to carry out his frenzied commands.

His impact in Dallas is already obvious.

The Cowboys will be switching to the 4-3 defense Kiffin and Marinelli crafted so successfully in Tampa. DeMarcus Ware, a seven-time Pro Bowl outside linebacker, is being asked to make the transition to defensive end.