The triple major winner from Fiji withdrew from the PGA Tour's Phoenix Open yesterday after admitting he used the substance that has been found to contain a banned growth hormone.
"While I have used deer antler spray, at no time was I aware that it may contain a substance that is banned under the PGA Tour Anti-Doping Policy," said Singh, who could be hit with a worldwide suspension, in a statement. "I am shocked that deer antler spray may contain a banned substance and am angry I've put myself in this position. I've been in contact with the PGA Tour and am co-operating with their review of this matter. I'll not be commenting further."
Since drug testing was introduced in golf in 2008, only one PGA Tour member, Doug Barron, has been banned for violating the code. The journeyman pro was given a one-year suspension after failing a drugs test at the St Jude Classic in 2009 but now, golf officials are facing up to the prospect of taking action against a player who spent 32 weeks as the world No.1 between 2004 and 2005.
Deer antler spray is manufactured by the controversial company, Sports With Alternatives To Steroids (SWATS) and it has been found to contain the banned IGF-1, a natural anabolic hormone that stimulates muscle growth.
In the wake of Singh's admission, Sir Bob Charles, who won the Open in 1963 at Royal Lytham, announced last night that he had used and promoted a deer antler spray for more than two decades.
The New Zealander said he was "totally unaware of illegal substances . . . being in the horn or the antler of the deer," while he added "I take one or two deer velvet capsules daily and have been doing so for 20 years or more."