IRVING, Texas– Here is what you should like most about the first week of OTAs for the Dallas Cowboys.

         That Tony Romo is back at quarterback. That Dez Bryant is nearly back at wide receiver, and will be so in plenty of time for the Sept. 11 season opener. Orlando Scandrick will be back at corner, too.

         Let's see, Tyrone Crawford is out there playing without a torn rotator cuff. Morris Claiborne is back out there without that injured hamstring, and by the way, at left cornerback, with Brandon Carr on the right side and Josh Thomas in the slot for now on the first defense. Byron Jones is where he belongs at free safety. Terrell McClain is back, adding depth to the defensive line interior. Like the looks of Cedric Thornton, Maliek Collins and Charles Tapper, too.

         Oh, and Ezekiel. All you needed to do was watch him on a couple of carries jump in the hole and scoot to thoroughly understand he's not just any ol' running back.

         Sort of a reminder of what the Cowboys were missing or trying to play through for the majority of last season, along with some impressive add-ons for this season.

         Now then, here is what you should dislike most during the first of their three, three-a-week "voluntary" OTA sessions, concluding then with the mandatory three-day minicamp in the middle of June.

         And this will have nothing to do with backup offensive guard Ronald Leary withholding services, his new agent demanding his client be traded, a request and maneuver without one ounce of leverage since he's already signed his one-year, $2.553 million restricted free-agent tender absent $1 of guaranteed money or services desperately needed. Their only hope for movement would be someone such as Chaz Green, who hasn't played a down of football since the end of the 2014 college season, shows enough ability to not only play some tackle, but also guard, too, thus making Leary somewhat expendable for a modest draft choice in return.

         No, this worry has to do with the absence of Rolando McClain, who always seems to have something getting in the way of offseason football, practicing or just simply weight and conditioning. This time it's personal family issues he's trying to take care of, though Cowboys head coach Jason Garrett says he should be back at The Ranch next week.

         OK, that would be fine, or at least palatable. But his offseason work at The Ranch has been sporadic, and the biggest worry would be conditioning and physical shape. Last thing you need is for someone to jump back in there after extended inactivity and pull a hamstring or groin. We've seen similar nagging injuries occur with guys who hadn't been working out diligently or returning from injury and then hurting something else.

         Ugh!

         This is one reason why the Cowboys only have signed McClain to his third consecutive one-year contract, this one though including a $750,000 signing bonus, a $1.25 million base salary and a per-game incentive that could bump his contract to $4 million, with another potential $1 million in playing-time incentives included, those incentives the much-needed dangling carrot you'd hope serve as motivation.

         That's not a huge expenditure or gamble on a player of his caliber.

         And to me, those final four words there are the key: Player of his caliber. Which makes me think of what Cowboys owner Jerry Jones said prior to the NFL Draft when talking about either signing free agents or selecting players with shaky backgrounds, explaining how important availability is when gambling on one of these guys.

         See, the Cowboys just don't have another player with his potential impact at middle linebacker now that they have settled on Sean Lee playing the weak side, where he produced his first Pro Bowl season and one of the best by a Cowboys linebacker in quite some time. McClain's presence in the middle made the move possible.

         And to understand his impact in the middle, just realize that last year, having played only 11 games – he was suspended the first four games for violation of the league's substance abuse program – he finished with 97 tackles, nine for losses, two sacks, 10 quarterback pressures and that interception returned for a touchdown against Miami. If you factor his 11-game tackle total over a 16-game season, he would have finished with 141. That's robust.

         Plus, just his presence in the middle grabs offensive coordinators' attention. He has a suddenness to his game. A physical presence. Nastiness, and in this case, a good thing in football. This Cowboys defense needs that, at least until second-round draft choice Jaylon Smith's peroneal nerve totally re-fires, and odds are that might not happen until the 2017 season.

         That's why defensive coordinator Rod Marinelli says of McClain's early absence, "Can't wait to get him back." Consider that double-sided impatience: Get him back for his talents and to make sure he's getting in better shape than those who saw him back in April when offseason activity resumed here at The Ranch.

         For now, Anthony Hitchens is in the middle with the first group. And that's not a bad thing. Seems as though he's a better middle linebacker than one on the strong side, where that guy has to play more on the line of scrimmage. Hitchens is instinctive and plays well in space. Plus the coaching staff is pretty excited about what they've seen from him so far this offseason, not to mention he's here and working.

         Also why McClain's availability is so important to this team this season? To me, with Romo and Dez back healthy, the addition of Elliott to last year's fractured running back corps, along with Alfred Morris and maybe at some point Lance Dunbar's return, this offense will be awfully good again.[embeddedad0]

         That means if this defense improves, this team will improve, the same thought this time last year before the injuries struck the starting quarterback and wide receiver, the third-down running back and then the starting running back and leader in rushing touchdowns plummets into oblivion six games in, never to return.

         McClain, of sound mind and body, helps make this defense better. That's why he needs to be here, working, training, practicing, even if it's in these voluntary workouts. Now, day after Memorial Day. If not, then look, only attending the mandatory minicamp (June 14-16) and then showing up July 28 for the start of training camp would be a precursor for something else happening.

         And that's what would worry me most if I were you.