For the second time in four years, Cal coach Sonny Dykes has fired his defensive coordinator. And for the second time, he was really left with no choice.

Art Kaufman had three years to turn around the absolute mess he inherited following a historically bad 2013 season, but after two years of moderate improvement, the Bears took a significant step back this year. The 42.6 points per game Cal allowed this season was the second-worst mark nationally and only three teams allowed more yards per game.

"We thank Art for the progress he was able to help our program make, but we have decided that we need to go in a different direction and find new leadership at defensive coordinator," Dykes said in a statement. "We wish him the best in his future coaching endeavors."

He’s right. A change of direction was needed, but Cal’s problem on defense is far greater than X’s and O’s.

The year before he arrived in Berkeley, Kaufman coached the nation’s No. 9-ranked defense in Cincinnati, and was among the nominees for the Broyles Award, given to the nation’s top assistant, in 2011 at Texas Tech and 2012 at North Carolina. He knows defense. He knows how to coach defense.

Cal coach Sonny Dykes is again looking for a defensive coordinator. Robert Johnson/Icon Sportswire

Andy Buh, the coach Kaufman replaced, justifiably took a lot of heat when Cal allowed 45.9 points per game in his lone season coaching the defense, but he landed as the coordinator at Maryland this past year and helped the Terps reach a bowl game.

This is no longer about the defensive coordinator. It's about Dykes.

At this point in his career, he has a clear, deserved reputation as a head coach: His teams can score a lot of points, but they can’t stop anyone.

In his final year at Louisiana Tech before he was hired at Cal, his team led the nation in points per game (51.5), but only five teams allowed more (38.5).

At Cal, it has been more of the same.

In Dykes’ four seasons, there isn’t a Power 5 defense in the country that has allowed more points per drive than Cal. The 39.6 points per game it has allowed during that span is the fourth-worst average nationally.

Of the 43 teams in the country that have averaged more than 32 points per game in the last four years, only two have a losing record: Cal and Texas Tech.

This isn’t as simple as hiring a new coordinator and hoping for the best. There needs to be systemic changes: a greater emphasis on defensive players in recruiting and a top-down evaluation of everyone on the defensive staff. There isn’t an easy fix or a quick fix, but Colorado and Washington State are recent proof that the type of defensive turnaround Cal needs is possible.

Still, the obvious next question is: Who will replace Kaufman?

It's easy to toss around names for various reasons, but the combination of Dykes’ history with defense and his poorly-kept secret of wanting to coach elsewhere limits the job’s appeal.

Unlike Pac-12 North rival Oregon, Cal won’t be able to throw a lot of money at a sitting defensive coordinator at a Power 5 school and convince them to come to Berkeley. It will likely need to find someone out of job (as was the case with Kaufman), hire a promising position coach from elsewhere (as Washington State did with Alex Grinch) or give a bigger platform to a lower-level coordinator.

There is not one right way to make this hire, but Dykes had better make it work because if it doesn't, he won't get another opportunity.