IRVING, Texas -- If Dez Bryant's threat to "not be there" means missing the regular-season opener on Sept. 13 against the New York Giants, then what happens with the Dallas Cowboys?

The coaches lauded the work of Terrance Williams in Bryant's absence during the offseason program. Williams became the de facto leader of the wide receiver room. He and Tony Romo were much more in-tune with each other.

That wasn't always the case with the two.

The Cowboys will have a difficult time matching Dez Bryant's production if he misses any regular-season games. Kevin Jairaj/USA TODAY Sports

"He's not only taken a tremendous leadership role in the group, really setting the example of how you do things, he's expanded his route inventory," wide receivers coach Derek Dooley said at the conclusion of last month's minicamp. "He's played X. He's played Z. He's played in the slot and every day he went out there and was the same player. Every route, every opportunity he had he took advantage of it. So he's made a big jump this offseason."

Devin Street worked with the starters with Bryant absent. He had just two catches as a rookie in 2014 but the coaches liked his development through the year. Getting the extra work with Romo in the spring will help his development this year. Coaches say players make the biggest jumps between their rookie and second seasons. While any work would have been good work for Street, having that work come with Romo is an added bonus.

Cole Beasley would continue to serve as the No. 3 receiver in the slot, so his role would essentially be the same, but it could change how much the Cowboys use three wide receiver formations.

They could also use tight end Gavin Escobar more in a receiver role, which would likely eat more into Street's snaps than Beasley's.

The Cowboys signed former first-round pick A.J. Jenkins earlier in the offseason to help with the inexperience at the position with Bryant missing. Do they look for another veteran if Bryant is not with the team at the start of training camp?

Receivers like James Jones, Wes Welker and Reggie Wayne remain unsigned, but their best days are behind them. There could be other down-the-line moves the longer a potential Bryant absence goes.

The remaining wide receiver options are not tested. The Cowboys signed George Farmer, Antwan Goodley and Lucky Whitehead to undrafted deals with moderate guaranteed money. Undrafted free agents Nick Harwell and Deontay Greenberry also had some moments in the organized team activities and minicamp.

But counting on any of them to even contribute a fraction of what Bryant can do is a little much.

Without Bryant, the Cowboys could lean even more on the run. They want to continue their run-first mentality in 2015 anyway. But how much more difficult would it be to run the ball without Bryant on the field to prevent the extra defender in the box?

Romo's job would be even more difficult.

Romo has combined with top receivers throughout his time as the Cowboys' starter from Terrell Owens to Miles Austin to Bryant and put up big numbers. But he has also made it work with his Nos. 2 and 3 receivers, like Terry Glenn, Patrick Crayton, Laurent Robinson and Williams over the years.

The Cowboys' offense won't be elite without Bryant if he misses games. They wouldn't have Bryant's 16 touchdown catches or DeMarco Murray's 1,845 yards.

Good luck with that.