A familiar visitor to these parts threw the 100th US Open into chaos here at Pebble Beach yesterday. Dense coastal fog, which caused play to be abandoned shortly before 4.0 p.m. (local time) on Thursday afternoon returned with a vengeance yesterday morning to scupper hopes of catching up on missed play.

It meant that Darren Clarke, for instance, had only a 40-minute break after playing the back nine of his first round before setting off on his second. Yet his mood remained buoyant, largely due to a spectacular eagle two at the 15th - a repeat of the exploit which fired Tiger Woods to victory here in the AT&T Pro-Am last February.

For Woods, it was a holed wedge. With the benefit of considerably more run on the ball, however, Clarke needed only a lob-wedge to cover the 92 yards to the pin. The ball bounced once and he watched delightedly as it settled into the slope of the green to run unerringly for the cup.

It effectively wiped out the two strokes he was over par from his opening nine on Thursday. And pars on the other eight holes - he missed a six-footer for birdie on the last - left him well pleased with a solid 71. "I had several birdie chances this morning buy it was about the right result for the way I played," he said afterwards. From a position of three over par after his first three holes on Thursday, one could well understand that assessment. But the Tyrone-man seemed to have difficulty in achieving a productive consistency. So it was that in the second round, he bogeyed the sixth and seventh and then birdied the eighth to be one over par for the championship after 27 holes.

As it happened, Clarke was in the critical three-ball which led to the suspension of play on Thursday afternoon. When they reached the 10th tee, one of the Irishman's playing partners, Jeff Maggert, complained to USGA official Tom Meeks that he couldn't see where he intended to hit his drive. After surveying the situation, Meeks concurred and called the players in.

After a hurried consultation, it was then decided to open the practice grounds at Pebble and Spyglass Hill at 5.45 yesterday morning for the benefit of the 75 players who still had to finish the second round. But plans for that and a 6.45 a.m. start, went by the board when the fog returned. "This is going to become known as the Foggy Open," said Meeks with a wry smile.

The upshot was that in a revised draw sheet, the last threeball were scheduled to start their second round at 6.0 p.m. local time yesterday which meant that in a best-case scenario, they could have hoped to complete no more than nine holes. So, the halfway cut is unlikely to be made until sometime late this morning. Either way, the organisers are quite prepared to extend the championship to Monday if necessary.

While this is the first time that weather has interrupted play in four US Open stagings at this venue, the same cannot be said of other events here. The AT&T Pro-Am, played in late January and early February, is a frequent sufferer and the tournament was wiped out after two rounds in 1996. Then, last August, the US Amateur was held up for about 20 minutes because of fog.

The really disturbing part, however, is that events so far may turn out to be the good news. More coastal fog is predicted for the weekend and the possibility of further delays will hinge on its density.

But the players are coping, though 60-year-old Jack Nicklaus wasn't over-enamoured of the idea of playing 27 holes yesterday. "You get a lot of this kind of weather at Pebble Beach at this time of year," he said, after completing an opening 73 and then setting off once more into a benign afternoon with temperatures in the mid-60s.

Incidentally, when Nicklaus found himself in the slot in the draw which would normally have been reserved for the defending champion, he decided to pay his own, special tribute to the late Payne Stewart. So he turned to the starter, Ron Reed, and said: "Ron, would you object to a moment of silence before I hit, in honour of Payne?"

According to Nicklaus, the starter replied: "No, I think that would be very appropriate." And the Bear added: "So that's what I did."

Advancing years were borne lightly, however, by Hale Irwin who did a fine job of defending his three-under-par status, in the second round. It could be claimed that the 55-year-old set off with something of an advantage, however, insofar as he became the oldest winner of this title when he captured for a third time at Medinah in 1990, when he was aged 45 years and 15 days.

Nick Faldo had five holes to complete then play was halted on Thursday and, as it happened, he slipped back from four under par to finish with a 69. But it could have been worse, given that a double-bogey at the short 17th, where a two-iron tee-shot found a plugged lie in a bunker, left him on one under.

Then came the sort of break that is wonderfully welcome to a player in his current plight. After an over-zealous sandwedge third had left him 30 feet from the pin at the last, he proceeded to roll in the putt for an improbable birdie finish. "It was hard work out there," he said ruefully.

The key question regarding the 42-year-old Englishman, however, was whether this represented yet another false dawn - if that's not an inappropriate metaphor in the circumstances. And he gave his dwindling supporters precious little to enthuse about in a scrappy front nine to his second round in which he carded three bogeys as against two birdies to reach the turn at one under for the championship.

Colin Montgomerie also had mixed fortunes. Two visits to the left rough led to a double-bogey seven at the long 14th as he progressed to a moderate, opening 73. And the Scot was so discouraged by this that he declined to comment before setting off again.

Yet after two holes of his second round, Monty had got back to level-par for the championship. Which does much to illustrate the sort of emotional instability which has created such a forbidding burden for him in the major championships.