Defensive end Brett Keisel is approaching unrestricted free agency under the assumption he's the player the Steelers believe they can least afford to lose. "That's what I've heard, that I'm the priority," Keisel said Monday. "A little birdie told me that, but birds can bring all kinds of different messages, so who knows?" Keisel, a fourth-year pro from BYU, earned a base salary of $656,000 in 2005. Negotiations on a new deal have yet to commence, he said.