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Earlier this offseason, Dallas Cowboys quarterback Ben DiNucci said his poor play as a rookie "wasn't me out there," but the lie detector determined that was a lie. As it turns out, based upon rapidly mounting evidence, it actually was him out there -- as in there hasn't been a single thing he's done in the 2021 preseason that counteracts the inconsistency, inaccuracy and poor decision making he put on display in two games last year. Contrarily, Cooper Rush is seeing his stock rise to the point that he's suddenly pushed expected backup Garrett Gilbert against the ropes, and that sets the stage for a final showdown on Sunday.

That's when the Cowboys will take on the Jacksonville Jaguars, and it's also what head coach Mike McCarthy and offensive coordinator Kellen Moore will use to finally decide who'll play QB2 behind Dak Prescott who, by the way, threw a total of 52 passes in pregame warmups on Saturday, completing 51 of them on a variety of different routes to different targets.

"We're about to have to incarcerate him, I think. He's that ready to go," said team exec Stephen Jones last week of Prescott to 105.3FM the Fan.

With the two-time Pro Bowler on track to play in Week 1 against Tom Brady and the Tampa Bay Buccaneers, the good news is the Cowboys have no concerns about who'll start. And while they hope they'll never again need to play a backup QB, having a quality one can make or break a season -- as they learned the hard way in 2020. After seeing DiNucci effectively make it a two-man race between Rush and Gilbert, by tossing three interceptions against the Houston Texans on Saturday, this is the week the position has to get sorted out.

The Cowboys might carry three quarterbacks in 2021, which isn't unheard of, but they're absolutely not carrying four.

"I've always said this, especially at this time: It's up to the players to decide who is on the 53," said McCarthy after Saturday's loss, when asked about the shaping of the final 53-man roster. "Three quarterbacks, 10 linemen, 10 D-linemen, 11 [defensive backs] -- that's why you go about it."

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It's possible DiNucci isn't completely out of the door just yet, but it's equally possible he is. Should the former be true, he'll have one more chance to prove he's at least worth continued development (something he's yet to make anyone believe), and that could land him on what is now expanded and revised practice squad rules around the league.

"Now, this is unique as far as the roster development compared to prior years, and I'm talking about last year and this year -- the [16-man practice squad]," McCarthy added. "You have the 16 on practice squad. You have your veteran practice squad opportunities. So, a lot of moving parts to this, and we talked about this the other day: our goal is make sure we come out of here with 58 players that we know we have here right now."

That said, DiNucci's stat line this preseason amounts to 255 passing yards with only one touchdown to four interceptions. 

At one point this offseason, the Cowboys worked out several veteran backup QBs that included Brett Hundley and Jeff Driskel, but instead decided none of them were an upgrade over the current bullpen. Both Hundley and Driskel have since found new NFL homes, but that doesn't disqualify the Cowboys from keeping an eye on the market as a whole -- should things go wildly awry behind Prescott in the near future.

"I think, I mean, that's what Will McClay and the staff's always done. That's why we work the hours that we do, and I think every NFL player and NFL personnel department, you're always comparing guys to the rest of the league."

So, which Cowboys quarterback will be on the sidelines watching Prescott work in 2021? What was once a clear answer in Gilbert is now muddied by his early game fumble against the Texans along with Rush completing nine of his 12 passes for 97 yards and two touchdowns to zero interceptions. 

"We have one more week," said McCarthy. "We're going to need it."

The lie detector determined McCarthy is telling the truth.

How far will Dallas go this season?