PITTSBURGH (AP) — Le'Veon Bell's next season with the Pittsburgh Steelers will almost certainly be his last.

The Pro Bowl running back and the defending AFC North champions failed to reach an agreement on a new contract by Monday's deadline, meaning he will play under the franchise tag for a second straight year and hit the open market next spring.

Bell tweeted that he "both sides worked extremely hard" to try and find common ground but ultimately could not.

"The NFL is a hard business at times ... to the fans that had hope, I'm sorry we let you down but trust me, 2018 will be my best season to date," Bell posted.

The 26-year-old Bell is one of the league's most versatile players and he has long maintained he wants to be paid accordingly. In addition to serving as a workhorse in the backfield — his 321 rushing attempts last season led the NFL — he also caught 85 passes, good enough for 10th in the league.

Steelers general manager Kevin Colbert said the team will make another attempt to re-sign Bell in the 2019 offseason, but another Pro Bowl-type season by Bell would likely make him too expensive.

Bell will make $14.5 million whenever he signs his franchise tender, which likely won't be until the end of training camp. It's the path Bell followed last summer after the Steelers placed the franchise tag on him for the first time.

He arrived the weekend after the end of the exhibition season and got off to a bit of a slow start before finding his footing in October while helping the Steelers to a second straight division title and fourth consecutive playoff appearance.

The depth chart behind Bell is uneven at best. James Conner showed signs during his rookie season last fall before a knee injury. The team drafted Jaylen Samuels — who did a little bit of everything at North Carolina State — in the fifth round this spring. Samuels was an effective receiver for the Wolfpack but he lacks Bell's unique overall skillset.

One the Steelers — barring an unusual turn of events — will have in the fold for just one more year.

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