Vikings' Peterson tears ACL

Jason Cole
Yahoo Sports

Minnesota Vikings running back Adrian Peterson tore the anterior cruciate ligament in his left knee during a 33-26 win over the Washington Redskins, a team PR official confirmed via Twitter on Saturday.

Peterson also tore his MCL, according to a source.

It was feared that Peterson tore the ACL after the result of an on-field test that was conducted after Peterson was carried off the field. Peterson suffered the injury during a three-yard run in which he was tackled by Redskins safety DeJon Gomes.

"You never know for sure, but it didn't sound good the way everybody was talking," a team source said.

[ Slideshow: Check out photos of hurt Adrian Peterson ]

The injury will likely require surgery and roughly six months of rehabilitation (the source wrote: "Maybe more than that too").

"Anytime you take a blow to the knee like that, you’re concerned about the ACL, MCL," Peterson told the Associated Press as he stood on crutches in the locker room. "I'm trying to stay as positive as I can."

Peterson, who missed three games earlier this season with a high left ankle sprain, finished the day with 38 yards and scored a touchdown. For the season, he has 970 yards and 12 touchdowns. Peterson will miss next week's season finale against the Chicago Bears and will face a long process to get ready for next season.

Prior to the season, Peterson signed a seven-year, $100 million contract extension. The deal included $36 million guaranteed.

It is the second straight season in which Peterson was sidelined against the Redskins. He suffered a right ankle injury in the second quarter of last year's matchup against Washington and did not return.

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