MINNEAPOLIS -- Minnesota Vikings running back Adrian Peterson said he sprained his left ankle in the second quarter of the team's 38-17 win over the Chicago Bears on Sunday, though Peterson returned to the game late in the third quarter.

Sources told ESPN's Josina Anderson on Monday that Peterson will "be ready to go" Sunday against the New York Giants.

Peterson's left ankle bent awkwardly as Bears defensive end Pernell McPhee dragged him down following a 9-yard gain. Peterson went to the trainer's table but quickly hopped off and appeared to try to walk off the injury. He went to the locker room with Vikings officials after consulting with athletic trainer Eric Sugarman.

Adrian Peterson returns to the game against the Bears on Sunday in the third quarter. The Vikings running back had injured his left ankle in the second quarter. AP Photo/Ann Heisenfelt

"You could call it an alligator tackle; they snap on, and they twist," Peterson said. "A guy rolled me up."

Asked about the severity of the injury, Peterson said, "I really can't pinpoint it right now, but it was definitely an ankle sprain. I was able to get out and kind of get it loose, and I got loose enough after about the first series [of the third quarter] and was able to get back out there."

Peterson said he did not need X-rays, adding, "The bone and everything is OK." He said he wasn't sure if he would need an MRI.

The NFL's leading rusher, Peterson finished the day with 63 yards on 18 carries and has 1,314 yards for the season, taking a 9-yard lead over Tampa Bay's Doug Martin with two weeks to go. Peterson admitted he was initially worried about being able to return to the game, but he had six carries in the second half.

"I came in and was sitting around for a little bit," he said. "They taped it up, and it got a little stiff on me. When I got out and was able to move around and get the muscles and tendons back firing, it got to a point where I was OK and I could go."