They subsequently agreed to a one-year deal with veteran guard Trai Turner, agent Drew Rosenhaus told NFL Network.
DeCastro, 31, has played his entire nine-season career with the Steelers. He has been named All-Pro three times and earned his sixth straight Pro Bowl nod last season. Steelers general manager Kevin Colbert released a statement praising DeCastro, but the reason for his release was not immediately clear.
"David was without a doubt one of the premier offensive linemen during his time with us," Colbert said, per the statement. "He helped us win a lot of football games, but it was David's consistency, reliability and professionalism that stood out more than anything else. We wish him the best moving forward in his career."
Why did Steelers cut DeCastro?
Per Over the Cap, the Steelers save $8.75 million in cap space while taking on $5.5 million in dead money with the transaction. But the prime free agency window is closed. The timing of the move doesn't suggest a pure salary cap motive. And Pittsburgh will have to pay Turner. The terms of his deal weren't immediately reported.
DeCastro dealt with an ankle injury last season that continues to linger and is "evaluating his future," per NFL Network's Mike Garafolo. With the season approaching, the Steelers may have made the move to ensure they have somebody to play the position this fall.
Nearly complete revamp of Steelers offensive line
DeCastro's departure is the latest in an almost complete revamp of Pittsburgh's offensive line. Longtime left tackle starter Alejandro Villanueva left in free agency to join the rival Baltimore Ravens, while 11-year veteran Maurkice Pouncey retired. Left guard Matt Feiler also left in free agency to join the Los Angeles Chargers.
Turner, 28, arrives in Pittsburgh after a single season with the Chargers. He previously made five Pro Bowls as a member of the Carolina Panthers.
With an aging Ben Roethlisberger, tumult on the offensive line and stiff competition, oddsmakers don't like Pittsburgh's chances of repeating as AFC North champions. The Steelers are listed a +400 to win the division behind the favored Ravens and Cleveland Browns.
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