The Pittsburgh Steelers and running back Le'Veon Bell were unable to reach reach a long-term contract extension, meaning he'll be playing under the $14.3 million franchise tag in 2018.

But according to NFL Network's Ian Rapoport, the Steelers offered Bell a massive five-year extension worth $70 million, but it wasn't good enough to please the three-time Pro Bowler.

Atlanta Falcons running back Devonta Freeman became the NFL's highest-paid player at the position last year when he signed a five-year extension worth $41.25 million. Bell is by far the league's best running back, but players at the position tend to fade when they turn 30, and he's now 26 years of age.

The Steelers gave Bell an extremely generous offer, one that could have set the market for future running back contracts. But that wasn't enough for Bell, who shared this statement on his Twitter page.

ESPN's Adam Schefter reported earlier that he thought Bell would maybe sit out half of the 2018 season if a deal wasn't reached. Instead, it sounds like Bell will play throughout the campaign and try to set himself up for a mega contract next offseason in March.

The Steelers have a lengthy history of not giving into the contract demands of their top players. Quarterback Ben Roethlisberger hasn't been a problem, as he continually restructures his deal to help the team save cap space. In this case, Bell wasn't willing to take a pay cut, and he looks poised to land the biggest running back deal in franchise history.

Credit: Charles LeClaire-USA TODAY Sports

The Steelers seem confident that they'll be able to replace the league's best running back, though it won't be an easy task. Bell has accumulated over 1,000 rushing yards and 600-plus receiving yards in three of the last four seasons, earning a reputation as the league's most complete, all-around running back.

But if Bell and the Steelers can add a seventh Super Bowl to the franchise's trophy room, then perhaps they'll find a way to figure out a long-term extension.

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