(Sam Greenwood/Getty) Born in New Mexico to an African-American father and a Mexican-American mother, Foster says he spent his high school days dreaming of becoming a professional football player. One of his teachers didn't like his chances: "She kind of laughed and asked me what else I wanted to do." When Foster tried out for his school football team, coaches told him he wasn't good enough to be a running back.

(Harry How/Getty) After his parents divorced, Foster went to live with his father, who moved from Albuquerque, New Mexico to San Diego, California. During Foster's senior year in San Diego, he was given a chance to play running back. Foster never looked back, bruising his way to various school honors and a scholarship to Tennessee.

(Bob Levey/Getty) When Foster went undrafted, he decided to try out for the Houston Texans. He didn't make the official roster. After spending most of the year on the Texans' practice squad, Foster was eventually called up late in the 2009 season. The following season, he earned the starting job. In his first start for the Texans, Foster racked up a record-breaking 231 yards and scored three touchdowns. By the end of the season, Foster was the NFL rushing champ.

(Bob Levey/Getty) Earlier this year, Foster missed the beginning of the 2011 season with a hamstring injury. Not only would Foster have to prove that his breakthrough season wasn't a fluke, he would have to show he could recover from injury and remain a force in the NFL. Thirteen games into the season, Foster has proved his doubters wrong: he's less than 50 yards away from his second 1,000+ yard season and best of all, he's helped the Texans make the playoffs for the first time in franchise history.

(Frederick M. Brown/Getty) Foster knows it's rare to go from being undrafted to being a superstar, but he attributes his success to hard work, not luck: "I don't think anything will just happen. The universe will throw somebody a bone every now and then, and you win the lottery. But for the most part, you get in this life what you put in."