Dak Prescott turned down a contract offer that would've averaged $30 million annually, according to NFL Network's Jane Slater.

Slater reported Prescott is looking to get $40 million a year, which would make him the highest-paid player in the league, per Spotrac. Tom Brady and Russell Willson own the current mark as they each earn $35 million a season.

A source refuted the rumor to Pro Football Talk:

Former Cowboys wide receiver Dez Bryant weighed in with his thoughts:

Prescott is entering the final year of his contract. If he is hopeful of hitting $40 million, his demand would reflect how quarterbacks often have all of the leverage when the time comes to sign an extension. The scarcity of proven options at the position puts front offices at a distinct disadvantage.

That's why Carson Wentz can get a four-year, $128 million deal from the Philadelphia Eagles despite missing eight games, including all of the last two playoff runs, between 2017-18.

In this case, however, Prescott might be overestimating his worth.

Prescott has thrown for 10,876 yards, 67 touchdowns and 25 interceptions while running for 944 yards and 18 scores so far. The 2016 fourth-round pick ranked 25th in DYAR (defense-adjusted yards above replacement) among the 34 quarterbacks with at least 200 passing attempts in 2018, per Football Outsiders.

Still, the ongoing negotiations highlight how the Cowboys are in such a difficult spot. Eliot Shorr-Parks of 94WIP.com contrasted this situation with that of Wentz and the Eagles, who finalized their agreement in June:

In addition to Prescott, Amari Cooper will hit the open market in 2020 and be in a position to command a salary commensurate with the best-compensated receivers. Michael Thomas reset the market on his five-year, $96.25 million extension with the New Orleans Saints.

Ezekiel Elliott is another wild card. Elliott still has two years remaining on his deal but continues to hold out for a new contract.

Keeping all three players is possible but would likely require cost-cutting measures elsewhere on the roster.

Assuming Prescott and the Cowboys don't strike a deal before Dallas' first regular-season game Sept. 8, the quarterback's future will be one of the biggest storylines surrounding the team in 2019.