Sapp was a bully, too, charge some of his former teammates, the Tampa Bay Times reported Wednesday.
"Some guys teeter around that edge" of bullying, Sapp said. "But Richie? Nobody has ever had a question that Richie was a dirtbag."
Incognito is accused of using a racial slur against teammate Jonathan Martin. Martin has temporarily left the Dolphins and Incognito has been suspended.
Sapp also was a bully when he was with the Bucs, said former fellow players Keyshawn Johnson, a Bucs receiver from 2000-2003, and Chidi Ahanotu, a Bucs defensive end from 1993-2000.
Writing on Facebook, Ahanotu said he and several other Bucs "all confronted Sapp & had physical altercations of varying degrees with Sapp. Virtually nothing was off limits to Sapp's verbal attacks & belittling of his teammates & front office staff."
Johnson told a San Francisco television station that Sapp used to bully Ahanotu.
"So one day, you know what Ahanotu did? He got up and he told him, 'Get your you-know-what in the middle of the floor right now. I'm tired of it.' At that point, guess what Sapp did? He sat down. And then everybody else in the locker room, me, the Derrick Brookses, the Brian Kellys, we all said, 'Good for you, man.'"
Responding to the allegations, Sapp told espn.com, "I've been called everything under the sun in this town. This is the first time I've ever heard that, and why do you think that is?"