Mack announced his retirement Thursday, Michael Silver of NFL Network reports.

The 49ers and Mack agreed to a reworked deal Thursday, lowering his base salary for 2022 and 2023, Field Yates of ESPN reports.

Mack is mulling retirement this offseason, but 49ers GM John Lynch said Wednesday he expects the center to play in 2022, David Lombardi of The Athletic reports.

Mack signed with the 49ers on Wednesday, Ian Rapoport of NFL Network reports.

Mack was activated from the Falcons' reserve/COVID list Wednesday.

Mack (concussion), who sat out Atlanta's final two games to close out the regular season, started 14 games in 2020.

Mack (concussion/illness) is slated to miss Sunday's game against the Buccaneers, William McFadden of AtlantaFalcons.com reports.

Mack (concussIon) was placed on the reserve/COVID-19 list Thursday, Will McFadden of the Falcons' official site reports.

Mack (concussion) was held to limited participation during Wednesday's practice, Jason Butt of The Atlanta Journal-Constitution reports.

Mack (concussion) has been ruled out for Sunday's game against the Chiefs, D. Orlando Ledbetter of the Atlanta Journal-Constitution reports.