The Cowboys lost their most indispensable player, quarterback Tony Romo, for an estimated 6 to 10 weeks to a fractured vertebra in his back thanks to a hit by Seahawks defensive end Cliff Avril on the third play of Thursday's night preseason game.

Shorthanded already at quarterback because of Kellen Moore's potentially season ending broken right leg, the Cowboys are left with fourth-round pick Dak Prescott to assume Romo's job.

Prescott has been sensational this preseason. He is completing 78 percent of his passes (39 of 50) for 454 yards with five touchdowns and no interceptions to post a 137.8 passer rating. Prescott also has two rushing touchdowns. It remains to be seen whether Prescott can duplicate his preseason success against vanilla defenses when defensive coordinators are game-planning for him and disguising coverages.

Romo missed 12 games last season with a broken collarbone, which derailed Dallas' chances to repeat as NFC East champions. The Cowboys were 1-11 without him.

The Cowboys have some tough decisions to make, now and in the long term. Here's a look at a couple of the more immediate concerns.

1. The injured reserve decision

The Cowboys have to decide whether to place Romo on short-term injured reserve (IR). Each team can pick one player on IR after the final roster cutdown to 53 players on Sept. 3 to return to practice after missing a minimum of six weeks. This player can return to game action two weeks later. Prior to this year's slight change to the NFL constitution and bylaws about short-term IR, teams had to specify whether a player could return when put on the list. The new rule provides for flexibility since the choice of which player will return is made later.

Romo may be an ideal candidate because of his expected recovery time. Putting Romo on IR would remove the temptation for Dallas to rush him back on the field before he has sufficiently recovered, especially if Prescott falters, when the risk of re-injury would be greater. IR would mean the earliest Romo could play would be in Week 9, Nov. 6, against the Cleveland Browns.

Considering that Dallas' bye is in Week 7, Romo would only be missing one game, the Week 8 contest vs. the Philadelphia Eagles, over the most optimistic estimated return time by going on IR.

Tony Romo Cowboys
Putting Romo on IR would remove the temptation for Dallas to rush him back on the field. USATSI

Romo's injury should end any chances Moore has of returning this season since he'll be headed to IR. The most viable scenario for Moore to possibly play is if Romo goes on IR and can't return anywhere close to the projected timetable and Moore's own recovery is much faster than anticipated.

2. Finding another QB (trade vs. free agent)

It will be interesting to see whether Dallas waits for cutdowns or renews the efforts to make a trade for another quarterback that began early in the month when Moore was first injured. Dallas had discussions with the Browns about journeyman, 14-year veteran Josh McCown that went nowhere.

Michael Vick, Josh Freeman, Charlie Whitehurst, Tarvaris Jackson, Matt Flynn, Jimmy Clausen and T.J. Yates are currently available. Signing one of the players would probably only be for their applicable league minimum salary.

There should be more quarterbacks available once teams trim rosters from 90 players to 75 players by Tuesday's 4 p.m. ET deadline. It wouldn't be a surprise for Dallas to sign a temporary fix for the final preseason game Thursday since Jameill Showers, a second-year player, is the only other healthy quarterback on the roster besides Prescott.

Although Prescott is an inexperienced rookie, Dallas might sit him or play him sparingly to make sure he is ready to go for the regular season.

It wouldn't be surprising if the Cowboys signed a veteran like Tarvaris Jackson. USATSI

Adding a veteran with significant game action is preferable given the lack of experience of the team's remaining healthy quarterbacks. Knowing that Dallas needs another quarterback, those teams with good depth at the position will likely try to drive a hard bargain even for a player that could be on the roster bubble.

The Cleveland Browns (McCown or Austin Davis), Denver Broncos (Mark Sanchez) and New York Jets (Geno Smith or Bryce Petty) seem to be the most logical potential trade partners.

It shouldn't cost the Cowboys more than a late-round 2017 or 2018 draft pick to acquire a quarterback. At the end of the preseason in 2014, the Patriots received a 2016 seventh-round pick from the Houston Texans for Ryan Mallett, who was in the final year of his rookie contract. Dallas gave a 2017 fifth-round pick to the Buffalo Bills for Matt Cassel and a 2017 seventh-round pick in an early season trade last year.

The Cowboys might prefer to give up a player at one of their deeper positions, such as running back, instead of a draft pick. The selection of Ezekiel Elliott with the fourth overall pick in this year's NFL draft and free agent acquisition Alfred Morris resembling the three-time 1,000-yard back he was with the Washington Redskins could make Darren McFadden, who is out because of freak offseason accident injuring his elbow, a luxury.

Guard Ronald Leary could be trade bait for a veteran quarterback, if they choose that route. USATSI

Restricted free agent guard Ronald Leary is the odd man out on the offensive line because of La'el Collins. The Cowboys don't appear to have a realistic shot of keeping Leary beyond this season since he wants to be a starter.

Patience may be Dallas' best bet since the league trend is to go with two quarterbacks on the 53-man roster with a third on the practice squad. Sanchez may not survive the final cut in Denver. He was the offseason favorite to start but has fallen to third on the depth chart behind two players that haven't thrown an NFL regular-season pass in Trevor Siemian and 2016 first-round pick Paxton Lynch. Sanchez will be a lot cheaper as a street free agent than in a trade since he's scheduled to make $4.5 million.

Austin Davis is battling Cody Kessler, a third-round pick this year, to be Cleveland's third-string quarterback. He has 10 career starts, including eight with the Rams in 2014. Petty is making the decision about Ryan Fitzpatrick's primary backup difficult after a strong second preseason game last week against the Redskins.

A reunion with Brandon Weeden could be a possibility if the Houston Texans let him go. Weeden knows the offense, which would be one of his biggest selling points, because he recently spent a season and half with the Cowboys. He didn't win any of his three starts in place of an injured Romo in 2015 and was released during the middle of last season.