Head coach Mike Tomlin said signing the 30-year-old Keisel, who had been scheduled to earn $3.25 million in 2009, to a new deal was a no-brainer for the team.
"He's ridiculously competitive. He has a mean streak, something that is necessary to play the position that he plays," Tomlin said. "He takes a great deal of pride in his work and he doesn't care who gets the credit. A lot of times when you play defensive end in our scheme, it's a lot of dirty work, occupying blocks, playing with great pad level, creating opportunities for others, such as James Harrison and LaMarr Woodley, who benefit greatly from the work of our ends. He embraces all of that and does it with a smile on his face. He embodies the things that we value as a Pittsburgh Steeler."
Keisel, who has been a starter at right defensive end since 2006, is now under contract through 2013.
His signing is likely the last one the Steelers will make until the end of the 2009 season, leaving six starters – nose tackle Casey Hampton, running back Willie Parker, right tackle Willie Colon, free safety Ryan Clark, center Justin Hartwig and placekicker Jeff Reed – possibly playing their last season in Pittsburgh.
One 2008 starter who will not be playing for the Steelers this season will be Stapleton, who had surgery in early August on his right knee.
Stapleton, who made the final roster as an undrafted rookie in 2007, and started the final 12 regular season games and throughout the playoffs at right guard after Kendall Simmons was lost with an Achilles tendon injury.
He was slated to battle veteran Trai Essex for the starting position this season, but the play of Essex and the improvement of center/guard Doug Legursky gave the Steelers the option of shutting Stapleton down for the year.
"I've been pleased with what Doug Legursky has done," said Tomlin of the Marshall product. "He's taken advantage of an opportunity and shown position flexibility. He's played some center, he's played some guard. Really, when you look at where he is in his career and what he's doing, it kind of mirrors the situation Darnell was in a year ago. Darnell was a guy who was an undrafted second-year man in our program who showed some interior line flexibility and that's how he stuck and made it and on down the line, he had an opportunity to get in the lineup. A year ago, Darnell Stapleton was Doug Legursky."
The Steelers also released center Alex Stepanovich, wide receivers Martin Nance and Steven Black and safety Derrick Richardson to get down to the NFL roster limit of 75. The Steelers had until 4 p.m. Tuesday to make those moves.
Tomlin said he'll play the starters for only a series or two against Carolina as he takes on final look at the reserves to see who stands out as the team works to trim its roster to 53 players by the NFL deadline of 4 p.m. Saturday.
"There's no question that their experience is going to be a short one," Tomlin said of the starters. "That's the nature of it. They have some teammates who are fighting to the bitter end to play well and make this team. Those guys understand that. They are sensitive to that. They're going to be supportive of those guys."
Tomlin is hopeful that running back Willie Parker, defensive end Nick Eason and placekicker Jeff Reed, all of who missed Saturday's game against Buffalo, will be able to play against the Panthers.