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Updates from Thursday, Aug. 21

Brian McIntyre of NFL.com has the financial information on Keisel's deal:

Original Text

The Pittsburgh Steelers continued their flurry of mid-August activity Tuesday, coming to terms with defensive end Brett Keisel on a contract. Terms of the agreement have not been disclosed.

ESPN's Adam Schefter first reported the news:

The Steelers confirmed the move on Tuesday via the team's Twitter account:

Keisel spoke about his return in a team release as well:

“It means a lot to be back,” said Keisel, who spent the offseason as an unsigned free agent. “There really is no place like here, no place like home. It was tough, just the unknown. For them to give me the opportunity to come back means a lot to me and I can’t wait to get back to work. I still have a little time to not only get to know these men I am going to go to battle with, but just get back into football stuff. I feel great. I have been training my tail off with the thought that I am going to be back. It looks like all of that training has paid off.”

The Steelers previously announced a long-term contract extension for offensive tackle Marcus Gilbert on Tuesday afternoon.

Keisel, 35, has spent each of his 12 NFL seasons in Pittsburgh. A seventh-round pick in 2002, he's become a mainstay for the organization and resides in Pennsylvania. Kent Somers of the Arizona Republic reported the Cardinals attempted to have Keisel in for a workout following Darnell Dockett's injury but he declined.

Gene J. Puskar/Associated Press

The Steelers, who'd mostly shown tepid interest in having Keisel return since he hit free agency, scooped him up within hours of Arizona's interest leaking.

“We haven’t eliminated anybody from consideration because we don’t know what’s going to happen before the season," Steelers general manager Kevin Colbert told reporters last month. "Even into the season there’s been times when we’ve brought back veteran players due to injury."

Pittsburgh is yet to suffer any major injuries on the defensive line, but the Cardinals' interest likely expedited the push to sign Keisel. As Darin Gantt of Pro Football Talk notes, the timing might ultimately be beneficial for Keisel's aging body: "The move is a win-win, as Keisel lends some stability to a defensive line that lost some parts this offseason, and the timing kept him from having to go to training camp."

A starter each of the last eight seasons, Keisel will have some competition for playing time in 2014. The Steelers signed former Charger Cam Thomas to start on the right end and are expecting big things from Cameron Heyward, their 2011 first-round pick. Pittsburgh also drafted Stephon Tuitt in the second round this offseason with designs on developing him on the end.

In addition to providing depth, the Steelers are likely signing Keisel hoping his work ethic and knowledge of the system will rub off on the likes of Tuitt. The former Notre Dame star was a second-team All-American in 2012 but saw his draft stock drop after an injury-riddled and less effective junior season.

Bill Kostroun/Associated Press

Keisel, a defensive captain, has long been one of the most respected voices in the Steelers locker room. Even if his performance isn't on par with his peak, he'll be fine in a more limited capacity and could return to the starting lineup if Heyward struggles to excel in an expanded role.

Keisel made 29 combined tackles, a low since becoming a full-time starter, and four sacks in 12 games last season. Among the 24 3-4 defensive ends who received 50 percent or more of their team's defensive snaps, Keisel ranked 21st in run stop percentage, per Pro Football Focus (subscription required). Keisel remains an above-average pass-rusher for his position, typically picking up three or four sacks per season and applying steady pressure.

Still, his age has to be a concern for a team that looked to be on the downside in 2013. The Steelers were ranked 19th in Football Outsiders' defensive DVOA metric, the first time in Keisel's career they've ranked in the bottom half of the NFL. The struggles continued a slow decline of an aging unit in desperate need of its young guys to step up.

Signing Keisel is an indicator that perhaps Mike Tomlin isn't comfortable handing the keys over to the young bucks just yet.

Follow Tyler Conway (@tylerconway22) on Twitter.