Dak Prescott continues to assure that it will be a tough decision.
The Dallas rookie has yet to throw an interception while leading Dallas to a 4-1 start and he attempts to again avoid the key miscues when the Cowboys visit the Green Bay Packers on Sunday (4:25 p.m. ET, FOX).
Prescott ascended to the starting job after Romo broke a vertebra in his back during the preseason. He has displayed poise beyond his 23 years of age by completing 69 percent of his passes, and his ongoing streak of 155 attempts without an interception is a rookie record.
But that stellar start hasn't altered the outlook of Jones.
"Tony is our No. 1 quarterback. We're going to have the luxury of being able to, I think, see them both," Jones said. "I don't want to presume that Dak is going to be necessarily healthy, I don't want to presume anything like that.
"But I welcome the opportunity of having Dak playing at this level and Tony back in excellent health. It's going to be really special for the Cowboys."
The Packers (3-1) have no debate at quarterback with Aaron Rodgers firmly entrenched and the perennial Pro Bowler has seven touchdown passes against no interceptions in five career meetings against Dallas.
However, Rodgers is coming off a suspect performance against the New York Giants in which he was just 23-of-45 passing for 259 yards, two touchdowns and two interceptions.
The 259 yards do qualify as a season best for Rodgers, who has thrown nine touchdown passes against three interceptions.
Rodgers might be asked to throw more against the Cowboys with running back Eddie Lacy (ankle) ailing and James Starks (knee) ruled out after surgery.
Undrafted rookie Don Jackson might be promoted from the practice squad and Jackson has been receiving a crash course just in case Lacy (team-best 295 rushing yards) is unavailable.
"Well, it's going to have to be next guy up," Rodgers said. "We're going to have to see who that is and adjust accordingly. I'm thinking Eddie is going to be OK this week -- hopefully."
Rodgers also hopes receiver Randall Cobb (neck) is cleared to play after taking a hit late in the win over the Giants.
Green Bay's defense will face a challenge as it goes up against stellar Dallas rookie running back Ezekiel Elliott and the Cowboys' rugged offensive line.
Elliott leads the NFL with 546 rushing yards and is averaging 5.0 yards per carry with a hard-charging running style that includes power, speed and the occasional hurdle.
Yet the Packers feature the NFL's top-ranked rushing defense and the sensational performances through four games include superb figures such as allowing just 42.8 yards per game and 1.99 yards per carry.
"Always excited for a challenge," Elliott said. "That's what competitors love, to go out there and be challenged."
The longest gain allowed by the Packers is just 14 yards. The run defense was a weakness last season when the Packers allowed 119.1 yards per game, but that has certainly changed this season.
"They're really good in their base defense when they play their 3-4 (alignment) and they're awfully good when they play their nickel personnel," Dallas coach Jason Garrett said. "They have really active defensive linemen. They're active on the edges.
"The linebackers are around the football. They're just a very good defensive team and they stop the run really, really well."
Inside linebacker Jake Ryan leads the Packers with 29 tackles and outside linebacker Nick Perry has a team-best 4 1/2 sacks for a defense that is somehow receiving little attention for its strong play.
"We just want to continue to get better. We just want to continue to fly under the radar," veteran outside linebacker Julius Peppers said. "We don't want anybody to talk about us, to tell us how good we are."
It hasn't yet been determined whether the Green Bay secondary will be shadowing Cowboys receiver Dez Bryant on Sunday.
Bryant participated through a small portion of Wednesday's practice for his first work since injuring his right knee against Chicago on Sept. 25.
The Cowboys have taken the cautious approach with his injury and Bryant is fine with that.
"Yeah, I'm OK with it because we are sitting at 4-1," Bryant said. "We're doing an extremely great job. It's no need to rush things. Like I said, that plays a huge factor."
Weak-side linebacker Sean Lee (team-best 45 tackles) and strong safety Barry Church (37 stops) are enjoying strong seasons for the Dallas defense.
The Packers have won the past four meetings, including a 28-7 victory last season when Rodgers passed for 218 yards and two touchdowns.