Davenport, 27, spent his first four seasons with the Packers, collecting 1,068 yards and seven touchdowns in 39 career games. He ran for 105 yards and two TDs last year before suffering a season-ending ankle injury in early October. He was released by Green Bay on Sept. 2 in the team's final roster cutdown.
To make room for Davenport on the roster, the Steelers released rookie running back Patrick Cobbs, who was acquired in a trade with the New England Patriots a week ago.
The 247-pound Davenport figures to serve as a replacement for Bettis, who retired last February after ending his illustrious 13-year career by helping Pittsburgh to its fifth Super Bowl victory.
Nicknamed "The Bus" for his bruising running style, Bettis served primarily as a short-yardage back in the latter stages of his career and ran for 22 TDs over the last two campaigns. Last season, Bettis helped form a devastating power-speed combination with Willie Parker, who paced the team with 1,202 rushing yards.
Despite a 28-17 season-opening home victory over Miami on Thursday, Pittsburgh shied away from running the ball in short-yardage instances.
After earning a reputation for their smash-mouth style with Bettis, the Steelers ran the ball just once in their four third-down plays where they needed three yards or less for a first down.
Parker rushed for 115 yards but was thwarted on a key third-and-2 late in the fourth quarter.
Packers release Hawkins
As expected, the Green Bay Packers and Mike Hawkins reached an injury settlement, and the cornerback was placed on waivers today.
Hawkins was bothered by soreness in his knee, which caused him to miss a number of training camp practices. He also injured his hip in the final preseason game.
Hawkins was selected with the second of two picks in the fifth round of the 2005 NFL draft by the Packers. He was placed on the season-ending injured reserve on Sept. 2.