In July, Dallas cornerback Morris Claiborne acknowledged that 2013 was humiliating.

“It’s definitely embarrassing,” Claiborne said, “especially when you know the type of talent you have on the team, but it’s just not showing up.”

Tuesday, Claiborne delivered a crushing hit on Oakland tight end Mychal Rivera in a joint practice. The hit led to a brawl that nearly spilled over into the stands, featuring a Raiders fan swinging a helmet at a Dallas player. Given the outlook of the upcoming season, this likely won’t be the last time you’ll hear concern emanating from the franchise’s defense.

In October 2013 the Denver Broncos absolutely dismantled the Dallas Cowboy defense: 34 first downs, 9-13 third down efficiency, 517 total yards. Quarterback Tony Romo’s 506 yards and five touchdowns weren’t enough; neither was the 48 points they recorded. It wasn’t all that noteworthy, though, because this type of performance became habitual for Dallas in nearly all of their matchups.

The 2013 Cowboys’ defense finished last in the NFL in total defense for the first time since 1994, allowing 415 yards and 27 points per game. Defensive Coordinator Monta Kiffin (demoted to assistant head coach/defense in January) couldn’t manage to keep his unit above No. 27 in the NFL in either opponent rushing yards (128.5 per game) or opponent passing yards (286.8 per game). They gave up a franchise-worst 6,645 total yards (third-worst in NFL history), set records for futility and had one of the eight easiest schedules in the league.

This season, they have a daunting NFC East schedule and their non-division opponents include the 49ers, Saints, Seahawks, Bears and Colts.

Defensive end DeMarcus Ware—the man who likely will be remembered as the greatest pass-rusher in franchise history—was cut in March, and is now playing for Denver. He didn’t warrant the money he was requesting but his six sacks a season ago, still good for third-most on the team, will surely be missed. Defensive end Jason Hatcher the 2013 team leader in sacks (11) is gone, as are Jarius Wynn and Everette Brown.

Most notably, linebacker Sean Lee, who registered the second-most tackles (68), most interceptions (four) and highest WPA (1.69) on the team in 2013—had season-ending surgery to repair a torn anterior cruciate ligament in June.

Rather than fixing the fulcrum of their franchise, Dallas responded by drafting Notre Dame’s Zach Martin at tackle in the first round of the 2014 NFL draft, waiting till the second round to pick a defensive player. Their second round choice, Boise State linebacker Demarcus Lawrence, promptly broke his foot in late July and is out for eight to 12 weeks. On Tuesday, cornerback Orlando Scandrick was suspended for four games for testing positive for performance-enhancing drugs. Every game in the NFL season matter, but the four Scandrick’s missing seem particularly daunting: San Francisco, St. Louis, Tennessee and New Orleans.

In the first four games next season, Dallas will be missing 61.8 percent of its sack total and five of the 11 players who accrued 28 or more tackles a season ago. The unit looks destined to give up more than 30 points per game. Here are some projections merely based on what’s happened since 2010:

After a 2.4 percent decrease in allowed yard production from 2010 to 2011 (this was the year DeMarcus Ware posted 19 1/2 sacks and the Cowboys still went 8-8), the numbers begin to nosedive: 3.6 percent percent increase from 2011 to 2012, 16.8 percent increase from 2012 to 2013. Obviously this is heavily manipulated by last season’s travesty on the defensive end, but since 2010 this averages out to a 6 percent increase in allowed yard production each season. If Dallas were to continue the trend, they’d eclipse the New Orleans Saints worst defense of all-time by a single yard.

Since 2011, they Cowboys have also allowed opponents into the end zone exponentially more: 21.7 points per game in 2011, 25 points per game in 2012 and 27 points per game in 2013.

“We were last in the league in defense and we’re trying to be number one,” Claiborne said. “That’s our goal. We’re not shying away from it.”

This season’s unit is comically bare and the team hasn’t won more than eight games since 2009—in large part because of their defense. With a ransacked roster, no back end or starter-quality safeties and a difficult schedule, Dallas very well could be looking at the worst defense in the history of football in 2014.

Josh Planos has had his work featured at the Wall Street Journal, Chicago Tribune’s RedEye Chicago, Rivals, Denver Post, CBS Sports Radio, Fox Sports Radio, and ESPN Radio, and is currently a columnist for the ESPN TrueHoop Network and The Cauldron. He loves interacting with readers via Twitter (@JPlanos).