The owner and general manager's reasoning won't be much comfort to fans: He says they can't get worse than they were a year ago.
Dallas had the worst defense statistically in franchise history in 2013, including the first two 600-yard games the Cowboys have ever allowed. Dallas gave up an NFL-record 40 first downs in one of those games.
The most notable thing the Cowboys have done since the season ended is release franchise sacks leader DeMarcus Ware. And then Lee went down with a torn ligament in his left knee in the first offseason practice.
Jones acknowledges that his defensive roster isn't as good as it was at the start of last season. But he believes it's better than the injury-ravaged unit that finished the year.
''I can say it this year, we are better right now,'' Jones said this week during a three-day minicamp that wrapped up Thursday. ''Not on paper at the beginning of the season last year, but on paper right now relative to how we ended up last year.''
Jones says he's not counting on Lee being available in 2014, but isn't ruling out a return. The earliest Lee could expect to get back from anterior cruciate ligament surgery performed last week would be November.
Justin Durant has been working in Lee's spot during offseason practice. When Durant was hurt at the end of last year, rookie DeVonte Holloman started at middle linebacker.
The Cowboys added another candidate with fourth-round pick Anthony Hitchens, and they aren't ruling out additional moves before or after the start of training camp July 24 in Oxnard, California.
''If we had to play with the players we've got, I feel good that we could line up against San Francisco,'' Jones said, referring to the season opener Sept. 7.
The biggest overhaul on defense has been the front four. There's a chance end George Selvie will be the only starter who was on the roster a year ago, and he didn't even join the Cowboys until after training camp had opened last July.
Rookie second-round pick DeMarcus Lawrence will get a long look at right end, the premier pass-rushing spot, and free agents Henry Melton and Terrell McClain could be the interior starters.
The Cowboys are carrying 17 defensive linemen - more than any other position. But Jones said any future churning of the defensive front isn't likely to include Josh Brent, who is serving the final phase of punishment for his intoxication manslaughter conviction in the crash that killed teammate Jerry Brown.
Brent will eligible for release from a rehabilitation facility a few days after training camp is open. While executive vice president Stephen Jones has said the team isn't ruling out Brent's return, the owner says it's not really even worth discussing at the moment.
Since he retired a year ago, Brent would have to go through the NFL to play again, and he might face punishment under the league's personal conduct policy.
''His business with the league on reinstatement is just that - with the league,'' Jerry Jones said. ''We do want to support him, but it would be way ahead of ourselves to talk about when, if, and how he would join the Cowboys.''
Jones said the absence of backup quarterback Kyle Orton at the mandatory minicamp wasn't unexpected. Orton is reportedly considering retirement.
Orton started the season-ending loss to Philadelphia with a playoff berth on the line after Tony Romo had back surgery for a herniated disk sustained a week earlier against Washington.
Romo was held out of competitive situations throughout the offseason program, but Jones expects the limitations to be lifted when the Cowboys report to California.
''He's every place that we would hope he would be physically,'' Jones said. ''I like where we are with him.''
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