For Tiger Woods, the final round of a tournament has to be played in a red shirt, described by his mother Kultida as his power colour. For Seve Ballesteros, it was a navyblue sweater and slacks, along with a number four golf-ball as a protection against three-putting. Tom Weiskopf and Jack Nicklaus liked to play with three pennies (cents) in their pocket, while Weiskopf always used a broken tee on a par three.

Laura Davies has a distinct preference for white tees. Indeed she has been known, en route to a tournament venue, to drive back to her hotel, to replenish her supply.

Then there is Notah Begay, the full-blooded Native American who put some war-paint on his face before going into golf events during his college days at Stanford. Though he no longer uses the paint, Begay admits that he still says the prayer associated with the ancient practice. Only this week, Padraig Harrington regretted scoring a 67 in Wednesday's pro-am, on the grounds that it was difficult enough to shoot four good tournament rounds without "wasting" one beforehand. The fact is, golfers are notoriously superstitious. And Len Zaichkowsky, an American professor of sports psychology, believes it can have a damaging effect on performance. As he puts it: "You are relinquishing belief in your own abilities to some `unknown power' or luck."

According to Chambers dictionary, superstition is "any belief or attitude based on ignorance, that is inconsistent with the known laws of science or with what is generally considered in particular society as true and rational." In that context, how does one categorise the beliefs of Gary Player who claimed that God had ordained he would win the modern Grand Slam? The great deed was actually achieved at the US Open at Bellerive in 1965, after a play-off with Kel Nagle. But before the championship got under way, Player claimed that his name appeared, clear as daylight, in gold letters at the top of the leaderboard. Superstition or devout religious belief?

Professor Zaichkowsky claims such beliefs serve no useful purpose, even though they might have been adopted with the intention of reducing anxiety. "Superstitions have always been prominent among sports people," he says, "but the idea that a particular object or behaviour brings luck and causes you to play well, is a non-scientific attribution to success or failure".

Which is all very plausible. But perhaps the good professor will riddle me this. For 71 holes of the 1970 British Open, Doug Sanders stuck with his long-established practice of not using a white tee. But on the fateful 72nd, he made the curious decision to place a white tee in the ground. And the rest, as they say, is history.