Vikings running back Adrian Peterson is doubtful for Sunday's game at Atlanta because of a high ankle sprain. Peterson hasn't practiced all week after hurting his left ankle last week against Oakland. He was carted off the sideline Sunday and X-rays were negative. "With the limited amount of things he was able to do today, very, very doubtful he would make it, though," Minnesota coach Leslie Frazier said. Peterson is sixth in the NFL in rushing with 872 yards. He's tied with Philadelphia's LeSean McCoy with a league-leading 12 touchdowns.