The moves did not pay off immediately as the Cowboys allowed three points more per game and saw an increase of six points in opponent Total QBR allowed.
This offseason, the Cowboys underwent even more changes, but will these moves bring the defense back to respectability?
New defensive coordinator
The Cowboys parted ways with Rob Ryan as defensive coordinator after two seasons.
Under Ryan, the Cowboys never finished higher than 16th in points allowed for a single season.
Ryan’s replacement is 73-year-old Monte Kiffin, who last coached in the NFL in 2008.
Kiffin coached the Buccaneers’ defense from 1996 to 2008, with Tampa Bay finishing in the top 10 in points allowed in 12 of the 13 seasons.
His defenses in Tampa were particularly stingy against the pass. On average the Buccaneers finished fifth in pass yards allowed per game.
New Base Defense
Kiffin will transition the Cowboys from a base 3-4 defense to a base 4-3. The Cowboys played a 3-4 before Ryan’s arrival, and the switch will move former outside linebackers DeMarcus Ware and Anthony Spencer to defensive end.
Since the start of 2008, 14 teams have switched base defenses, which has generally led to positive results.
In the first season following the switch, teams have allowed on average 1.3 points per game fewer and have seen a more than three point average improvement in Total QBR allowed.
Last season, the Cowboys revamped their cornerbacks. This season, the Cowboys will have a new look at the safety positions.
The Cowboys signed free agent Will Allen and drafted J.J. Wilcox in the third round of the 2013 NFL Draft. In addition, Dallas parted ways with Gerald Sensabaugh, who played 93 percent of the Cowboys’ defensive snaps last season.
The Cowboys’ new safeties will need to do a better job defending the deep ball. Only three teams allowed a worse completion percentage on passes more than 20 yards downfield last season, and the Cowboys were the only team without an interception on those passes.
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