PITTSBURGH (AP) — The Pittsburgh Steelers on Thursday released six-time Pro Bowl guard David DeCastro in a surprise move.

The 31-year-old DeCastro attended the team’s mandatory minicamp last week but did not participate in full-team drills.

DeCastro, the team’s first-round pick in the 2012 draft, spent nine years with the Steelers. He was named All-Pro following the 2015 and 2017 seasons while playing on one of the most dominant offensive lines in the league. DeCastro was entering the final season of a five-year $50-million contract he signed in 2017.

The decision does free up some salary-cap space for the Steelers to find a replacement, but DeCastro’s solid play on the field and presence in the locker room deals a significant blow to what is now a very young offensive line group.

“David was without a doubt one of the premier offensive linemen during his time with us,” general manager Kevin Colbert said in a 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.”

DeCastro expressed frustration last December with the disjointed 2020 season. The Steelers won the AFC North while playing most of their home games in an empty Heinz Field because of COVID-19 protocols.

“You’re like, ‘What are we doing out here?'” DeCastro said at the time. “I don’t like to make excuses because we’re professionals and stuff but we’re still human. We have emotions and not having fans there, it’s just tough.”

DeCastro’s abrupt departure means the Steelers will have an almost completely rebuilt offensive line entering 2021. Veteran center Maurkice Pouncey retired in January, left tackle Alejandro Villaneuva signed with Baltimore and left guard Matt Feilier is now with the Los Angeles Chargers.

Zach Banner is the only starter from the offensive line group that walked onto the field for Week 1 in 2020 who will be back this season, and Banner is recovering from major knee surgery after going down in the opener against the New York Giants.

The Steelers drafted center Kendrick Green in the third round to take over for Pouncey. Kevin Dotson will take over at one of the guard spots, with B.J. Finney figuring to be the frontrunner to take over the other one unless Pittsburgh finds someone on the market.

t like Trai Turner, who was released in March by the Chargers.

DeCastro missed the first two games of 2020 with lingering knee issues but appeared in 13 of Pittsburgh’s final 14 games. Steelers head coach Mike Tomlin did not address that status of DeCastro’s health at the end of minicamp.

“If I thought injury circumstances or reasons why people were not participating were significant, I would share them with you, but I’m not going to address day to day like things in this environment,” Tomlin said. “It’s not required.”