The Steelers cut Averett (undisclosed) from their practice squad Monday with an injury designation, per the NFL's transaction log.
Averett is expected to sign a contract with the Steelers on Sunday, Chris Halicke of DKPittsburghSports.com reports.
Detroit signed Averett to its practice squad Tuesday, Tom Pelissero of NFL Network reports.
Averett agreed to a one-year deal with the 49ers on Thursday.
Las Vegas placed Averett (toe) on its injured reserve list Tuesday ahead of Sunday's game versus the Chargers, Josh Dubow of The Associated Press reports.
Averett has left Sunday's game against the Seahawks early due to a toe injury.
Averett (thumb) was activated from injured reserve Saturday, Aaron Wilson of ProFootballNetwork.com reports.
Averett (thumb) was placed on injured reserve Monday.
Averett was diagnosed with a broken thumb Monday and will undergo surgery, Ian Rapoport of NFL Network reports.