(CNN) -- Former world No. 1 Tiger Woods has pulled out of next week's PGA Tour event at Quail Hollow due to a knee injury.
The American sprained a medial collateral ligament sprain in his left knee and also mildly strained his left Achilles tendon at the Masters in Augusta this month.
The 35-year-old suffered the problems while hitting a difficult second shot from the pine straw under the Eisenhower tree left of the fairway at No. 17 during the third round, his website reported on Tuesday.
He was able to continue playing, finishing tied for fourth for the second year in a row, but doctors later advised that he rest and receive treatment.
Woods hopes to be back "in a few weeks" according to his website, meaning he may miss the May 12-15 Players' Championship but should be fit for the U.S. Open on June 16-19.
"I personally contacted tournament officials and expressed my regret in not being able to play," said Woods, who won the 2007 Quail Hollow Championship but missed the cut last year as Northern Ireland's Rory McIlroy triumphed on U.S. soil for the first time.
"This is an outstanding event, but I must follow doctors' orders to get better."
Woods also commented on his Twitter page, writing: "Minor injury keeps me from playing Wells Fargo next week. Apologies to tourney & fans, but working hard to get healthy."
Woods has dropped to sixth in the world rankings since losing his No. 1 spot to England's Lee Westwood last October, having been at the summit for a record 281 consecutive weeks.
He did not play at the Texas Open or Heritage tournament after the Masters, and is still seeking his first tournament victory since November 2009.
Westwood, meanwhile, regained the top ranking from Germany's Martin Kaymer after winning the Indonesia Masters on Sunday -- his 38th birthday.