KUSA—A month ago, during the NFL Combine, John Elway was interested in Tony Romo, if not completely sold.

But in the hours leading up to the start of NFL free agency, Elway cooled off considerably, multiple sources told 9NEWS.

The Dallas Cowboys are expected to release their veteran quarterback on Tuesday, although that transaction would coincide with reports Romo is retiring as a football player because of health concerns and enticing offers to move directly into broadcasting. Romo reportedly will replace Phil Simms as the lead color commentator for CBS.

Romo’s retirement means Trevor Siemian is safe as a Denver Broncos quarterback. Had the Broncos wound up with Romo, there was a chance Siemian would have been traded. The feeling would have been three’s a crowd, especially when one of the quarterbacks, Paxton Lynch, was a first-round draft pick last year.

Now, there’s no doubt: Siemian and Lynch will compete for the Broncos’ starting quarterback position in 2017. The competition will start, if only in intangible ways, Monday when the Broncos report for the start of their offseason program at the team’s UCHealth Training Center.

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Per multiple sources close to the Broncos’ situation, the team’s plan, as always, was to first wait until the Cowboys released their veteran quarterback. Elway, the Denver Broncos’ general manager, was interested in checking out Romo in the days leading up to the start of free agency on March 9.

If Romo were a free agent, Elway was expected to bring Romo in for a visit for not only a full medical check but to also measure how committed the quarterback was to winning a Super Bowl.

It was never certain Elway would have signed Romo. The only certainty was Elway at one point was ready to explore the possibility.

Elway wanted no part of acquiring Romo through trade for two reasons. One, the final three years of the quarterback’s contract -- $14 million in 2017, $19.5 million in 2018 and $20.5 million in 2019 – would have been difficult to restructure within the confines of the Broncos’ budget.

The Broncos have roughly $16.5 million available in cap space and roughly $7 million of that is set aside to sign their draft picks.

And two, Elway values his draft picks. He did not want to surrender compensation when it wasn’t necessary.

But within a day or two of free agency, Elway backed off Romo, again, for two reasons. One, was the information Romo had been considering a move into the NFL broadcast booth. As evidenced by his conditional pursuit of San Francisco quarterback Colin Kaepernick last year, Elway is only interested in veteran players who are fully committed to the quest of winning a Super Bowl.

Money can’t be a factor, as it was with Kaepernick, who refused to take a pay cut. When it became known Romo was considering a TV career, it sent a signal he wasn’t all in on playing, much less finishing out his distinguished career with one more solid shot at winning a Super Bowl.

Another reason Elway backed off was closer inspection of Romo’s medical history. A source told 9NEWS it wasn’t necessarily Romo’s injury history that increasingly concerned the Broncos as how quickly those injuries occurred in recent years.

Romo, who turns 37 in 2 ½ weeks, broke his left collarbone twice in three games in 2015. After missing the rest of that season, he returned in 2016 only to suffer a compression fracture in his back during his second preseason series of 2016.

That’s pretty much three big hits and three breaks.

By the NFL owners’ meetings last week in Phoenix, Elway all but dismissed the possibility of the Broncos pursuing Romo.

“It’s not the intent to go that direction,’’ Elway said in an interview with 9NEWS.

The reason Elway once thought about pursuing Romo? The Broncos do not want to waste their terrific defense that was chiefly responsible for winning Super Bowl 50 to cap the 2015 season and still ranked No. 4 in total defense and points allowed last year.

Despite their fine defense last season, the Broncos missed the playoffs as their two young quarterbacks – the first-time playing Siemian and rookie Lynch – combined to go 9-7 last year. Down the stretch, the Broncos scored 10 points or less in three consecutive losses – an offensive skid not endured in Denver since 1966.

Meanwhile, the window on the Denver D’s excellence may be closing. Pass-rushing outside linebacker DeMarcus Ware, a former Cowboys star who did become a Bronco three years ago, retired. Star cornerback Aqib Talib is 31 and while he is still playing at an All Pro level, he also missed three games last season with a back injury. And strong safety T.J. Ward is in the final year of his contract.

Had the Broncos added Romo, they would have wanted Lynch to continue to develop as a backup for a year or two. There’s only so many backup reps to go around, which is why the team would have reluctantly considered moving Siemian.

The Romo scenario is now moot. Siemian is three months into his recovery from surgery to repair the damaged joint in his left, non-throwing shoulder.

Although he will proceed cautiously through the first six weeks of the team’s offseason program, he is expected to fully participate in the organized team activity practices (OTAs) that begin May 23.

It will be during OTAs that Lynch must demonstrate significant improvement if he is to have a legitimate chance at replacing Siemian as the Broncos’ starter. Vance Joseph, the Broncos’ first-year head coach, said the quarterback competition won’t begin in earnest until training camp and the preseason in late-July and August.

But Lynch must use the offseason to make up ground. Last season, Siemian posted an 8-6 record in the first 14 starts of his career, throwing for 3,401 yards and 18 touchdowns against 10 interceptions. The only reason Lynch got two starts was because Siemian was injured, first with his left shoulder and later with a sprained left foot.

Lynch played well off the bench in his NFL debut at Tampa Bay in week 4, but he was less effective in his two starts.

The only way Romo, Siemian and Lynch will be together for Broncos’ games this season is when Romo looks down from above in the broadcast booth alongside Jim Nantz.