2012 injury: Sprained knee ligament
The Buffalo Bills weren't happy when Fred Jackson went down in the season-opening defeat at the hands of the New York Jets in 2012, but C.J. Spiller's explosion as Jackson's replacement was a fine silver lining.
Although Jackson's 32, he's logged only 932 career carries, which is fewer than the career-carry totals of Arian Foster, Ray Rice, Matt Forte, Chris Johnson and many other prominent running backs.
When healthy, there aren't many runners more multi-faceted than Jackson, and although he lacks high-end athleticism and speed, he's deceptively elusive.
In 2011, ProFootballFocus.com (subscription required) gave Jackson the second-highest Elusiveness Rating among backs who played at least 25 percent of their respective team's snaps.
He's averaged nearly 35 grabs in his six NFL seasons as well.
Combine an injury-free Jackson coupled with Spiller, and the Bills will be primed to field one of the most dynamic rushing attacks in the NFL in 2013.