Tauscher has a torn ACL, the latest in a series of setbacks for a team that has lost three straight games and is a long shot to make the playoffs. It also leaves Tauscher's future uncertain because he will become a free agent after nine seasons in Green Bay.
Tauscher left Sunday's loss to the Houston Texans in the second quarter and was taken to the locker room for X-rays. He was replaced by third-year player Tony Moll.
"He's the guy you point to," Packers coach Mike McCarthy said. "He's a true pro."
Even so, the injury to the same ligament Tauscher tore in 2002 leaves his future in Green Bay up in the air.
Given his outgoing personality and state ties that include his college days at Wisconsin, Tauscher is one of the Packers' most recognizable and popular players -- especially in the post-Brett Favre era.
Tauscher has been reliable and rock-solid on the field, quietly holding opponents in check while rarely being called for penalties.