The move means Dansby has been offered a one-year deal worth just over $8 million, the average salary of the five highest-paid linebackers in the NFL last season. The Cardinals can continue to negotiate a long-term deal through July 15. If Dansby signs an offer sheet from another team, Arizona can match it or receive two first-round draft picks as compensation.
General manager Rod Graves called applying the franchise tag "a formality."
"It allows us to retain his rights to some degree and continue to negotiate with him for a long-term deal," Graves told The Associated Press.
He said he is optimistic a multiyear agreement can be reached. Graves said he spoke with Dansby's agent Kirk Wood on Thursday.
"As I've said before, my discussions with Kirk Wood have been favorable," Graves said. "There was no surprise on either side, and we anticipated it even as far back as a month ago."
Dansby led the team in tackles with 117 despite missing two games because of injury. He also had 3.5 sacks, three interceptions and four forced fumbles.
The 6-foot-4, 250-pound former second-round pick moved from outside linebacker to inside under new coach Ken Whisenhunt last season to make better use of his speed and playmaking ability. A second-round draft pick out of Auburn in 2004, Dansby has 382 tackles in 58 NFL games.
Copyright 2008 by The Associated Press