Dr. James Andrew was astonished to find that Adrian Peterson's knee had as much wear and tear as a "newborn baby" when he operated on the freakish tailback late last December. "I can't believe it," Andrews told Peterson's parents. "For this guy to have played as much football as he's played his whole life, and not to have hardly any wear and tear, it's incredible. I've never seen a football player, especially one who runs and cuts as much as he does, with a knee in that condition." Peterson gives the doctor credit, but insists he's just different -- "my family and genetics. Just how my body is built." Rotoworld's Pat Daugherty suggests Peterson's knees are made of rare metals found on a comet that crashed to Earth in a Norwegian forest.