#2 in total yards (#1 in attempts so that may offer some insight into what he's saying now) but #14 in YPC and then with his influence #26 in 2014.
If you believe in the running game then you bring in players like Incognito, McCoy and Taylor draft guys like Miller. During Marrone's tenure they were drafting WRs and QBs instead.
You also install a system like Roman had with multiple schemes and options so that you are difficult to defend. Heck, they even brought in WRs who were run specialists like Tate and Harvin. Everything was about helping the running game. That's how you become #1 in YPC and total yards for two straight seasons.
Now, whether you can win a Super Bowl this way any more is a different question...