There's more to this than a win over the Giants. Shanahan makes a statement
49ers news: Alex Mack reworked deal has retirement overtones
From Jimmy Garoppolo to Trey Lance to Deebo Samuel: Resetting 49ers' offseason - The Athletic
Center Alex Mack announces retirement after 13 NFL seasons - ESPN
Alex Mack: Breaking News, Rumors & Highlights
49ers news: Alex Mack makes retirement decision
49ers' Alex Mack announces retirement: 'I am so grateful to the game of football'
49ers roster: How to replace C Alex Mack after retirement
49ers sign Trent Williams to historic deal — and he may bring another Pro Bowl lineman with him – Daily Democrat