2015: Murphy deftly handled tackle duties, while Garnett's 321-pound frame turned opponents into rag dolls on a regular basis. McCaffrey frequently credited these linemen for the massive holes they opened up, and quarterback Kevin Hogan was certainly thrilled with the solid pass protection he enjoyed during his career season.

To make matters even more challenging, the Cardinal must also replace the retired Shuler, who communicated calls to the entire line from the center position. This is a major rebuilding effort.

Stepping in: LG Brandon Fanaika, OT Casey Tucker, OT David Bright, and C Jesse Burkett

Stanford has developed a reputation for recruiting and developing very well along the offensive line, and that's a big reason why the Cardinal have won three of the past four Pac-12 championships. Offensive coordinator Mike Bloomgren,who also coaches the line, is spending this offseason finding the right combination to assuage the losses of Garnett, Murphy and Shuler. Stanford hopes it discovers the magic formula earlier than the last time the Cardinal were breaking in a crew of new linemen: It took the unit a large part of the season to jell in 2014, and that led to a handful of losses.

This time around, the Cardinal hope that either Tucker (who started at right tackle last season) or Bright can fill Murphy's spot on the left side, while Fanaika may have the unenviable job of succeeding Garnett. Burkett is set to follow in Shuler's footsteps, though right guard Johnny Caspers may also see some time at center. The ultimate key to success up front