The marks were coming steadily now as the sleek, black yacht worked the final miles to the finish line and safe harbor in Key West.

John the navigator popped up from below every two or three minutes. "What's that mark?" he'd ask. "You get a three-second flashing green off the bow yet?"

The helmsman, John Marshall, battled the wheel in following winds and following seas. The dark spinnaker was full and the halyards and shrouds rattled and clanged against the tall aluminium mast.

It was 4 a.m. on Friday the 13th of January. To no one's surprise, Running Tide was running away from everyone else in the first big race of the Southern Ocean Racing Circuit.

No one, that is, but the race committee. "Did you get them on the radio yet?" demanded owner and chief signal-caller Al Van Metre.

"They won't answer," said John the navigator. "Probably sleeping."

For 18 hours Van Metre and his crew of 18 wind-worshippers had sliced south and then west through the rolling, warm waters of the Gulf Stream. They watched the garish opulence of the Lauderdale-Miami shore slide by, then the low green profile of the Keys. The light gave out and they mapped their course along a pearly string of land lights to the right and the endless empty rise and fall of the sea off the port beam.

At the start there had been the mad chaos of nearly a dozen big and complicated speeding sailboats tossing on their keels in a wild effort to be first across the line.

Van Metre' son, Beau, was steering the aluminum-hulled Running Tide. There were moments it seemed he would run her smack into the stern of the high-sided 60-footer Sirona. Orders and speeding boats were coming from every quarter when the gun finally sounded and Beau turned her hard and slipped across the line at the head of the pack and fartest upwind. Perfect.

"That was nothing," said mid-deck hand Timmy Kerns. "Beau is famous for his hairy starts."

Once past the start, ocean sailboat racing develops into a war of attrition. One by one the lesser craft fall back, either because they lack hull speed or design inadequacies prevent them from sailing "close to the wind."

The boat they generally fall behind is Running Tide, something of a legend in her time. Van Metre's sloop has none of the chopped-off, stumpy look of the latest speed sailors. She has lean, traditional lines. Somehow she stays at the top of the heap, year after year.

This season Van Metre, an Alexandria builder/developer, had her mast raised 7 1/2 feet at a cost of about $50,000 to keep her competitive. The Key West race was her trial run under the new rig.

She'd probably have licked everyone else even without the new mast, because Van Metre's chief rival was missing, Ted Turner, the America's Cup champion, didn't make the run for reasons unknown. He was supposed to be there, but Key West was only the final tuneup. The first of the six winter circuit races that count for points is Jan. 29 out of St. Petersburg.

"You want to know what kind of boat this is?" asked Tide crewman Bill Sharp. "Just write that she's a Turnereater 61."

These are competitive parts, and Al Van Metre is at home in them. He doesn't steer the boat and he doesn't fool with the grunt work of changing or trimming sails, navigating or rectifying foulups.But neither does he rest.

The silver-haired Van Metre spends his time in the cockpit, demanding readouts on wind speed, course, boat speed, angle of heel and jawing with Beau about tactics.

Van Metre gets his wish often enough. Last year Running Tide swept the Chesapeake bay fall series, knocking a little of the wind out of Turner's sails after the Atlantan's triumph in Newport. And tide has taken more than her share of Bermuda races, SORCs, Annapolis-to-Newports.

Key West was no different. Eight hours after the 10 a.m. start the visible rivals were down to two - Sirona out of San Francisco and Thunderhead, a New York boat.

By midnight only one set of mast-head and running lights was visible off the stern - Sirona's. Running Tide plowed along under full sail in 20-knot winds. She was clocking 9 knots-plus on the average, with spurts in excess of 10 knots. She carried a full main and two headsails.

Finally, the big boat swung around for the final run north to the finish line with Sirona a half-hour back. The spinnaker popped out of its bag as the boat ran before the wind. Quickly the buoys slipped by as land drew closer.

John, the navigator, was shouting into the radio mike. "Running Tide to committee. Is anybody up over there? This is ridiculous. Are you guys all asleep?"

Running Tide ran close to the breakwater that leads into the Key West Navy Yard. Up ahead there was a shape, the committee van, bedecked with flags and finish marker and utterly dark and empty.

The entire crew was on deck, celebrating and shouting at the van. Van Metre could barely believe it. "Get the horn," he told John the navigator who brought it up and squeezed out long, piercing blasts.

Lights blinked on in the van and sleepy forms came tumbling out. A spotlight cut across the water and found the numbers on Running Tide's mainsail. For the first time in 18 1/2 hours Van Metre smiled.

The sinnaker and jib dropped. The diesel coughed to life and Running Tide chugged into port. Committee types bobbed over on the pier, rubbing sleep from their eyes.

"Where do you want us," Van Metre asked.

"Wherever you want. Take the No. 1 place here next to the breakwater."

"That's what I like to hear," said crewman Bucky Weeks, shucking his oilskins."The No. 1 place."