Mark McCumber, golf's 5-foot-7 mighty mouse, roared his arrival on the PGA scene today, riding his prodigious 350-yard drives to a madcap one-shot victory in the Doral Open.

In the last four afternoons, the 27-year-old rookie rabbit has gone from mostly unknown struggler to budding folk hero.

A week ago, McCumber had never played the Blue Monster, had won only $14,000 in his eight-month PGA career and had only emotional calluses to show for his 20-year love-hate affair with golf.

McCumber not only won $45,000 today but established himself as perhaps the longest hitter in the game by outdistancing 6-foot-4, 225-pound Jim Dent in an all-day power duel.

To top it all, McCumber survived one of the dizziest 72nd holes of any tournament, sinking a seven-foot putt for a 279 total that preserved his one-shot win over Bill Rogers. Both shot 72 yesterday.

That final dramatic hole was indicative of McCumber's golfing audacity and his uninhibited charm.

"I stepped to the last tee with a two-shot lead," said McCumber, "but I told my caddie, 'Let's not sit on it.'"

McCumber lashed a typical scalding drive, but "that cautious blockout got in there at the last second."

The drive ended up far right in deep trash, offering the kind of shot golfers have nightmares about -- trees left, trees right, a tiny hole between and a vast lake straight ahead.

The crowd, which had fallen more in love with McCumber as the week wore on, gathered around, with many advising, "Lay up, Mark. Hit the wedge. Just play for bogey."

McCumber hitched his pants -- yup, that's right, just like Arnold Palmer -- and yanked out the three-iron.

"Richie," he said to his 6-foot-5 caddie with the shoulder-length white hair, "this one's either going on the green, or its gonna end up in somebody's pocket in the grandstand."

McCumber smoked the ball through the opening, but a wind, plus his own adrenaline, carried the ball entirely over the grandstand and toward the clubhouse.

"It ended up under a hotdog stand," McCumber said with a grin later. "But I knew the ruling all along. If you hit it over the stands, you get a free (no penalty) drop backwards along the line-sight. It was really a safe shot... as long as you're sure you know the rules."

For a moment, as he trudged to the ball, McCumber wondered, "Am I wrong?"

But he wasn't. After his free drop, McCumber's chip to the green and two putts for a secure bogey seemed certain.

"Then," he admitted, "I had my first negative thought in four days. I said to myself, 'Don't chunk this one in the trap.'"

As he addressed his ball, marshals held up their "Quiet" signs and 5,000 people went from muttering to funereal silence. McCumber looked up, blinked, then quipped, "Not that quiet, folks."

Then, that negative thought grabbed his brain.

"I chunked it anyway... right at the trap," he said. "If I'd hit it like any decent person, I'd have locked the tournament up right there."

The weak, chili-dipped shot hit the lip of the trap, then climbed up onto the fringe instead of dropping back into the sand and disaster.

A week of strain showed on McCumber's face. On Sunday night he had seen the Blue Monster for the first time. On Monday, fresh from not earning a single dollar in his previous six tournaments, McCumber qualified with the tour rabbits.

And now his slippery, 45-foot putt from the fringe slid seven feet past as the crowd groaned. Rogers, who won $114,000 last season, stood calmly in the center of the 18th fairway, waiting to make par and force a play-off.

Before the round, McCumber had begged his caddie, who had never worked a pro tournament before, to say one word to him in moments of crisis: "Isolate." That was McCumber's thought for the week -- ignore consequences, isolate each shot as a specific manageable challenge, rather than a culmination of a lifetime's work. Easily said. Almost impossible to do.

"I can't believe it," said McCumber, "but I actually did it. I knocked that sucker (the putt) right in the middle of the cup like it didn't mean a thing."

Then he danced. Then he jumped. Then he hopped like a frog. Then he hugged his caddy, lifting the giant into the air like he would later lift the huge Doral trophy over his head.

And then he waited -- to see if Rogers would do the nearly impossible: birdie the hole that gave the Blue Monster its name.

In the scorers' tent, McCumber collapsed, head in hands, as the huge Dent put an arm around him in that secluded spot and whispered in his ear.

"That man can flat hit the golf ball," said Dent, who had seen McCumber hit back-to-back drives of 350 and 367 yards through a cross wind on the long sixth and seventh holes."He's longer than me, no question about it.

"Longer with what? Longer with the driver. Longer with every club in the bag. He's just longer."

Then who is the tour's premiere power cat?

"Well," said Dent. "I used to be."

When Rogers had to scramble for par, leaving him a stroke ahead of late-charging Rod Curl for $27,000 and second place, McCumber hugged his wife and broke into tears.

"Darling, just breathe through your nose," she told him. "Compose yourself."

"This means everything to me," said McCumber, the self-taught blaster who once quit golf for four years ("just fed up"), then needed six tries to get through the tour qualifying school. "I don't know how long it will take me to realize what it means."

It means he ain't a rabbit no more.

While McCumber won this event with audacity, Rogers and third-round leader Alan Tapie lost it with timorous play at the nefarious 11th-12th-13th-hole corner of the course.

As Tapie faced a two-foot putt at 11, he and McCumber were tied at 10 under par with Rogers a stroke back. When Tapie fluffed the putt, it seemed to unhinge both him and Rogers.

Tapie blew sky high, going double bogey, bogey to disappear. On a day with five birdies, he also had seven bogeys and that double bogey.

Rogers three-putted the 12th, missing the cup from three feet, then stumbled through the par-3 13th ("I was totally asleep... that's where I lost this tournament") as he butchered a sand blast, then a chip, moving each shot only six feet.

When McCumber, among the leaders for 3 1/2 days, stepped to the 15th tee, he looked at the scoreboard for the first time in two hours and said, "My God, I'm four shots ahead."

Aggression was almost his undoing as he charged a 20-foot birdie putt at the 15th, and ended up three-putting. Rogers birdied behind him, cutting the lead to two, and McCumber was set for his 72nd-hole showdown with the Blue Monster.

As he walked off that final hole, McCumber thought of many things. This week he returns to his hometown of Jacksonville to play in the prestigious Tournament Players Championship. His brothers, construction engineers, are building the future "Players Club" course there, the home of the TPC in 1981.

"I'm going to Augusta (for the Masters)," McCumber remembered thinking.

Then a blond-haired man who finished 15 shots behind McCumber walked up and handed the little big man a fancy thick envelope -- an invitation to his exclusive tournament.

"Gee," said Mark McCumber, "thank you, Mr. Nicklaus."