Who Is Most to Blame for the 49ers’ Rushing Issues?

The San Francisco 49ers' running game is trending down. And I'm not just talking game by game. I'm talking year by year.

In 2012, the 49ers averaged the fourth-most rushing yards per game in the NFL with 155.7. Last year, they stayed in the top five with 137.6 yards per game on the ground.

This season? They're 12th in the league at 114.8. Worse yet, their yards-per-carry total has dropped from 5.1 in 2012 to 4.4 in 2013 to 4.0 in 2014.