Los Angeles ? The Nissan Open is headed for uncharted waters.

After four days at rainy Riviera Country Club, no one has played more than 37 holes.

And when rain suspended play a mere 30 minutes into the third round Sunday afternoon, officials conceded the possibility that the next hole anyone plays could be a sudden-death playoff between Adam Scott and Chad Campbell.

That’s assuming they can find a hole that’s not under water.

“We’re going to make every effort to play,” PGA Tour tournament director Mark Russell said. “We’re going to come back in the morning, try to finish the third round and see how it goes from there.”

Where the Nissan Open stood Sunday evening was baffling.

Campbell wound up getting the weekend off, which is golf vernacular for missing the cut. At the rain-delayed Nissan Open, that means he finished his second round Friday and hasn’t hit another shot since then, not even on the range.

“None yesterday and none today,” Campbell said. “That’s zero.”

Scott rarely feels a sense of urgency in the second round of any tournament, but this happened to be on a Sunday afternoon when he was one shot out of the lead, with clouds gathering on the horizon.

“I did think this may be the last putt of the week here,” Scott said. “So I better make it count.”

Scott rolled in a 20-foot birdie from the fringe on his final hole for a 5-under 66 in a second round that took him three days to complete. It put him at 9-under 133, tied with Campbell.

What happens next depends on the weather.

The forecast is for heavy rain overnight and throughout today, and Russell said Riviera was at the point where any rain would flood fairways and bunkers.

Players were to return today at 7:30 a.m. — only 12 of the 75 who made the cut teed off in the third round — and hope the forecast is wrong.

The goal is to complete at least 54 holes so it becomes an official tournament.

Otherwise, Russell said it could revert to a 36-hole tournament, the winner decided by a playoff.