EAST RUTHERFORD, N.J.—Frustrated by another late-season collapse, fed up by a three-year playoff drought, the Dallas Cowboys made a major move this off-season by hiring Monte Kiffin as their new defensive coordinator.

In tabbing Kiffin, who is 73, to oversee their defense, the Cowboys have recruited one of the National Football League's most experienced and influential coaches to transform a unit that surrendered an average of 25 points a game in 2012.

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