Pennington has agreed to terms on a one-year contract, and the deal is expected to be signed by Monday, a person familiar with the discussions said Saturday. The person spoke on condition of anonymity because the Dolphins hadn't announced an agreement.
The Dolphins did announce the signing of linebacker Karlos Dansby, who agreed to a $43 million, five-year contract Friday, the first day of free agency. The team did not host any visits by free agents Saturday.
Pennington is recovering from the third operation of his career on his throwing shoulder. Twice he has returned from injuries to win NFL Comeback Player of the Year, most recently in 2008, when he led the Dolphins to their first playoff berth in seven years.
After Pennington was sidelined last year, second-year pro Chad Henne staked a solid claim to the No. 1 job. Pennington will return as a backup to Henne, and the Dolphins also have Tyler Thigpen and Pat White at quarterback.
Pennington dislocated his shoulder in the third game last season at San Diego and required season-ending surgery. There was no muscle damage, and the repair wasn't as extensive as with his other operations.
Pennington was around the team late in the season, helped with game plans and has served as a mentor to Henne.
"I'm a loyal guy and I believe in this organization, and I enjoy this organization and this area," Pennington said late last season.