Tony Romo began his Cowboys career as an afterthought.

He departs nearly 14 years later as the most prolific quarterback in franchise history, the victim of injury and the meteoric rise of a rookie who wasn't meant to replace him for several years.

The club is set to release Romo as early as Thursday to coincide with the start of free agency, sources said. With hopes of a trade all but gone, sources said owner Jerry Jones informed the veteran quarterback of his decision in a conversation Tuesday.

Club officials had no public comment but have been leaning toward designating Romo as a June 1 cut. This allows the quarterback to search for another job immediately - Denver and Houston are potential landing spots - and splits his salary cap hit to the Cowboys over the next two seasons, freeing up $14 million in space for 2017.

The drawback: The club won't be able draw from that pool for player acquisition or to extend existing contracts for three months.

While no surprise, the parting is significant. Romo started 127 games over the last 11 seasons. Troy Aikman is the only quarterback in the franchise's rich history with more starts. Romo's run came to an unceremonious end last season because of another back injury and the success the team enjoyed with Dak Prescott.

The quarterback's time with the Cowboys has always been something of a Rohrshach test. Romo has hit one statistical high note after another during the regular season yet often fell flat in the postseason.

Is the lack of playoff success a reflection of Romo's shortcomings or an indictment of Jones' ability to surround the quarterback with enough talent? That debate will continue among fans as Romo ends his career in another city.

Romo leaves having thrown for 34,183 yards, more than any other quarterback in franchise history. He holds a majority of the club's career records, including scoring passes (248), games with a passer rating of 100 or greater (66), 300-yard games (46), games with three or more touchdowns (40), 20-plus touchdown seasons (7) and 400-yard games (5). He has completed 2,829 of 4,335 passes to rank second in both categories.

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Only two players in NFL history - Green Bay's Aaron Rodgers and New England's Tom Brady - boast a career quarterback rating higher than Romo's 97.1. He led the Cowboys to a 12-4 record and wild card playoff win over Detroit in his last full season as a starter.

These gaudy statistics are tempered by a lack of postseason success. Romo has presided over only two playoff wins in six attempts and has never taken the Cowboys past the second round of the playoffs.

Romo currently has a salary cap hit of $24.7 million. In the NFL's complex financial world, the Cowboys are actually on the hook for $19.6 million as they sever ties with Romo. If he's designated as a June 1 cut, as expected, the club will split that number over two seasons. He will count $10.7 million against the cap in '17 and $8.9 million next season.

An undrafted rookie out of Eastern Illinois, Romo spent a three-year apprenticeship with the Cowboys before ever throwing a regular season pass. He took over as the starter for veteran Drew Bledsoe in the second half of a game against the New York Giants in October 2006 and never looked back until he was replaced by Prescott.

Romo missed a career-high 12 games in 2015 after fracturing his clavicle. Twice. The quarterback had a cyst removed from his back in the spring of 2013 and missed the team's offseason program. Before the year was done he underwent surgery for a herniated disk, missing the final game of the regular season against Philadelphia when the team had a chance to win the division.

In November 2014, he missed a game after suffering a fracture of the transverse process in his back.

The bottom line: Romo, who turns 37 next month, has played in just five games the last two seasons. He has failed to finish three of the last five games he's started, including the preseason game in August against Seattle when he suffered an L1 compression fracture in his back, opening the door for Prescott's meteoric rise.

Club officials anticipated that Romo would return to the starting lineup when healthy. But Prescott performed at such a high level and the team was so successful it never happened.

The veteran quarterback gave what amounted to a concession speech in the days leading up to the team's game against Baltimore in mid-November. Romo read a statement that detailed his frustrations, pledged support to his heir apparent and elevated the importance of team over ego.

Romo's remarks pointedly sidestepped the long-term implications of the franchise's shift to Prescott. He walked a fine and often poignant line, saying his desire to compete still burned bright while making it clear he would not be a distraction in the final weeks and months as this team made its playoff push.

"He's earned the right to be our quarterback,'' Romo said of Prescott on that day.

He then paused, as he did at several other points during a statement that lasted just under five minutes.

"As hard as that is for me to say, he's earned that right," Romo continued. "He's guided our team to an 8-1 record and that's hard to do."

Now, Romo will be given the chance to end his career and chase that elusive playoff success somewhere else.

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