Fullback Owen Marecic, who played at Stanford under coach Jim Harbaugh, signed with the San Francisco 49ers on Tuesday.
Marecic replaces starting defensive lineman Ian Williams on the 53-man roster. Williams is out for the season with a broken ankle, an injury he suffered on a legal cut block at Seattle on Sunday night.
Marecic is the first player to play under Harbaugh in the NFL after doing the same at Stanford.
Marecic is a versatile player with some similarity to starting fullback Bruce Miller. Marecic has experience as a linebacker (at Stanford) and also lined up as an H-back or tight end at times for the Cardinal.
He's likely to begin in a special teams role but given his knowledge of the system, could get up to speed quickly in a greater role.
Former first-round pick Glenn Dorsey, in his first season with the 49ers after five seasons with the Kansas City Chiefs, has replaced Williams on the starting defensive line.