Zettel announced his retirement from football Friday, Nick Wagoner of ESPN.com reports.
Minnesota cut Zettel on Wednesday.
Zettel agreed to terms Wednesday on a contract with the Vikings, Courtney Cronin of ESPN.com reports.
Zettel signed a contract with the 49ers on Monday.
Zettel was waived by the Bengals on Tuesday.
Zettel signed a contract with the Bengals on Wednesday, Geoff Hobson of the Bengals' official site reports.
The Bengals cut Zettel on Monday, Ben Baby of ESPN.com reports.
Zettel signed a contract with the Bengals on Thursday.
Zettel was claimed by the Browns on Thursday.
Green was waived by the Lions on Wednesday, Field Yates of ESPN reports.