The Indianapolis Colts made two significant roster moves Wednesday morning, officially waiving DT Ed Johnson and agreeing to terms with K Matt Stover.

Johnson, who re-signed with the Colts shortly after this past April’s NFL Draft after being released a game into last season, had started the last four games after serving a one-game suspension under the NFL’s substance-abuse policy. Stover spent the last 18 seasons with Cleveland and Baltimore before becoming a free agent this past offseason.

The team announced that K Adam Vinatieri has undergone “successful arthroscopic surgery to his right knee to remove a piece of cartilage” and is expected to miss four-to-eight weeks. Vinatieri, a 14-year veteran in his fourth season with the Colts, spent the first three preseason games on the Physically Unable to Perform list after offseason knee and hip surgery.