Updated

Two days after Vijay Singh admitted using deer antler spray, a product that includes a banned substance under the PGA Tour's Anti-Doping Policy, he withdrew from the Phoenix Open before the first round started.

Singh, a two-time winner of the event, cited a back injury as the reason for this withdrawal.

The 49-year-old Fijian has yet to face the media after his admission to breaking the tour's Anti-Doping Policy. He did release a statement, which closed with him saying, "I will not be commenting further at this time."

Now that he has pulled out of the event, Singh gains some time for the uproar to die down. He is slated to play at Pebble Beach next week.

Singh's name was included in a "Sports Illustrated" story about the company S.W.A.T.S. -- Sports with Alternative to Steroids.

Though he stated, "at no time was I aware that it may contain a substance that is banned under the PGA Tour Anti-Doping Policy," Singh paid S.W.A.T.S. $9,000 for the spray and various other products, according to the "Sports Illustrated" story.

The tour notified players that the deer antler spray had been implicated in a positive drug test. According to the article, golfers were made aware of the spray's nature in 2011.

Singh has not failed a drug test to this point, so there is no telling if he will be suspended.