It is common in these stressful days to hear of medical experts recommending golf as a highly desirable form of relaxation. And in most circumstances, this is splendid advice, especially now that clubs have come to grips with the menace of the mobile phone.

Readers of this series will have discovered, however, that golf can, in extreme cases, be dangerous to one's health, as a certain Monsignor O'Leary discovered while having a friendly three-ball at the Overland Park GC in Memphis, Tennessee. The 72-year-old cleric was on the eighth green in the company of Dr W Millard (87) and Jim Breyspraak (66), when the incident occurred.

Without warning, a man emerged from bushes and demanded their wallets, but the brave senior citizens refused. In fact a scuffle ensued in which Dr Millard, despite his advanced years, succeeded in wrestling the thief to the ground.

At that point, Monsignor O'Leary, golf club in hand, made one of his better swings of the round, catching the intruder with a blow on the head. Stunned and surprised, he staggered whence he had come, empty-handed.

Enthusiasts of the quirkier side of the game have probably come across a fascinating little book by Chris Plumridge called Golf Disasters and Bizarre Records, which was published 13 years ago. The above story is recounted there, as well as this one involving the American professional, Lloyd Mangrum, winner of the 1946 US Open.

In the 1951 St Paul Open, Mangrum held a comfortable lead going into the final round, but before setting out, he received a very disturbing phone call. It seems that big money was riding on the outcome of the tournament and he was warned that if he didn't throw it, his wife would be killed.

But Mangrum, who was awarded two purple hearts while serving with the US forces during World War II, refused to be intimidated. Accompanied by a police guard, he won the tournament and emerged from the incident unscathed.

All of which leads us nicely to Southern Hills, which plays host to the US Open this week, when Tiger Woods defends the title. Tommy Bolt won the US Open there in 1958, but for the purposes of this exercise, the staging we are interested in was in 1977, when Hubert Green captured the title in extraordinary circumstances.

There was an unmistakeable irony about Green's appearance at the Senior British Open at Royal Co Down last July. With his pencil frame, lazy Alabama drawl and grey, fedora hat, he looked like the sort of individual who would have known what to do in a tricky, threatening situation. And the 1977 US Open at Southern Hills produced such a happening.

Among other things, the event was notable for a technicians' strike on ABC in the network's first 18-hole coverage of a US Open. And their final-day coverage was in progress for less than an hour when an uninvited stranger entered the control room and identified himself as an FBI agent.

His arrival coincided by a phone call from Sandy Tatum of the USGA informing producer Chuck Howard and ABC president Roone Arledge that a threat have been received on the life of the championship leader. And there were specific instructions that nothing should be said of the matter during the telecast.

In his superb book The US Open - Golf's Ultimate Challenge Robert Sommers informs us: "With 18 holes to play under searing heat at Southern Hills Country Club, Green was two strokes under par with 208 and leading Andy Bean by one stroke. They were paired together in the last round and as they drove from the 10th tee, an extraordinary meeting was taking place inside the Clubhouse.

"A Tulsa police lieutenant told the USGA's Harry Easterly, Sandy Tatum and P J Boatright a chilling story. A clerk in the Oklahoma City office of the FBI had answered a telephone call from a frantic woman who claimed three men were on their way to Tulsa to kill Hubert Green. `I know they're serious.' she cried. `They showed me their guns.'

"The nature of the meeting was kept secret, but several actions were taken. A phalanx of uniformed policemen suddenly sprang up around Green; the clubhouse was closed to everyone; plainclothesmen patrolled the gallery and a mysterious person materialised within the ABC control trailer where no outsider is permitted, and quietly gave orders . . . to instruct cameramen to scan the crowd around the 15th hole and not ask questions.

"Green obviously had to be told and he was already playing shaky golf. He had bogeyed the ninth and 10th and now Lou Graham was closing in."

Sommers goes on to tell us that as Graham walked towards the 18th tee, Green was leaving the 14th green. Easterly, Tatum and the police lieutenant called him aside and explained the threat and the reason for the unusual police presence.

The player was given three options: he could withdraw; he could ask for play to be suspended, or he could continue to play. Green chose to play on and even joked that the threat probably came from an old girlfriend. And nothing happened, leading those present to conclude that the entire episode was a hoax.

As for the championship: Green displayed remarkable self-control in a situation which would have been extremely testing, even without the death threat. He managed to card a par on the 15th and then birdied the long 16th where he had been in the rough. On the par-four 17th, he used his individualistic, spider-like putting stance to get down in two putts from 50 feet for a par.

With victory now in sight, nerves tightened even further with the result that Green was short with his approach to the testing, 449-yard 18th, where the ball came to rest in a greenside bunker. But a five would be sufficient, even though Graham had blistered the homeward journey in a four-under-par 31 strokes.

"Don't chunk it," Green muttered to himself as he dug his feet into the sand. But he did, leaving the ball 20 feet short of the target. Still, two putts would be enough for victory and after leaving his approach effort three and a half feet short, he finished the job and won by a stroke.

That was on June 19th. A little over two months later, on August 29th, Green completed an interesting double by capturing the Irish Open at Portmarnock where his aggregate of 284 was a record low for the event at the North Dublin venue, beating the target set by Syd Easterbrook in 1934.

Producer Chuck Howard kept his word not to tell his announcers about the threat, which was never mentioned on air. Shortly after the telecast had concluded, however, announcer Jim McKay was furious with his superiors after details of the drama came to light.

In fact Howard later admitted that it was several months before McKay, who considered himself to be an accomplished journalist, got over the matter. By that stage, Green had completed a memorable year by making his Ryder Cup debut at Royal Lytham, which included a singles victory over Eamonn Darcy, who had been tied 50th behind him at Portmarnock.