Many days this summer, Jaco Pastorius stalked the grounds of Fort Lauderdale's Holiday Park like a desperate hunter. Basketball under one arm, a copy of his old group Weather Report's 8:30 album and an acoustic guitar in the other, a headband holding stringy and unwashed hair in place, he appeared to the world a street bum trying to make contact with a reality he'd apparently lost.

"I'm the greatest musician on the planet," he once bragged, to no one in particular. A group of vagrants regularly gathered around him, and he relished the role of leader. "One of the greatest. The only people I respect are Miles Davis and Joe Zawinul. Write it down. By the way, happy Mother's Day. Ha! I'm working on a new album, Dixie Highway. It's gonna be bad."

Somebody asked why he's not playing more now. Dangerous question. "Because Miles and Gil Evans recorded my new tune in New York yesterday, shorty. And I was there. The Concorde flies out of Miami now."

The eyes are wide open and furious. A hurricane is trying to escape behind them. The same manic energy that made him one of this decade's most innovative young jazz musicians a few short years ago now howls out of control in every tortured sound he makes.

He is remembering Weather Report at the Havana Jam in 1979. "We opened the show with Black Market... right (running his finger down a list of cities on the record's inner sleeve)... there (stopping at Havana). So what, I'm living in a park. Parks are beautiful. I'm a musician. And I'm tired of dumb people who don't know where I come from."

It has been hard to know just where Jaco Pastorius, the Fort Lauderdale native who once overturned the jazz world with his approach to the electric bass, is coming from lately.

He's been at the top of his field. He's played music that is still considered ahead of its time. He is idolized by bassists around the world.

But he's paid a price for this enveloping success. When the same energy that drives his music runs unchecked, Pastorius becomes wild -- a victim of his own obsessions. Over the past seven years he has recorded only occasionally. Now 35, he's been treated for alcohol and substance abuse problems. He's served time in jail, and been institutionalized at Bellevue, New York's mental health treatment center.

Last week he wound up in intensive care at Broward General Medical Center, comatose following a run-in with the manager of a Wilton Manors private club. His condition Friday afternoon: Serious.

Those near Pastorius saw the incident as merely the latest -- and most serious -- scar from a much longer slide.

"It's the kind of thing we've almost expected," his brother, Gregory Pastorius, said recently.

Like many talented people -- particularly artists, more particularly musicians and most particularly jazz musicians -- Jaco Pastorius is driven by an almost mystical force, some inner voice that is always pushing for better: "Jaco has always tried to be the best," Gregory recalled. "Most valuable player in the all-star game, stuff like that."

With the force under control, Pastorius propelled himself to the heights of the music world. At age 26 in 1976, he was touring with Weather Report, the era's pioneering jazz fusion outfit, and at the same time planning his solo record and scheduling appearances with Joni Mitchell, Pat Metheny and others.

At times when he's lost control, the force has driven him to vent what most artists would recognize as logical frustrations -- say, the lack of widespread acceptance in his native country for his highly original work -- through the illogical comfort of alcohol. For him, that almost certainly spells trouble; he's been arrested nine times in 1987 alone on charges ranging from common vagrancy to driving a stolen car around the Holiday Park running track.

Jaco Pastorius has not learned to manage the curse that comes with his gift.

THE MELTDOWN BEGINS

The meltdown of John Francis Anthony Pastorius III begins in New York City sometime in 1984, when he dropped out of the music scene and began living in a cocaine-fueled underworld.

For weeks at a time, he made the street his home. He wore torn clothes and lived to play basketball at Greenwich Village's West Fourth Street park. He still played music occasionally but more than once left his instruments unattended and had them stolen.

Friends in the music community tried to help him. They encountered a difficult and stubborn man, the kind of guy you couldn't trust on a gig. As guitarist Hiram Bullock said: "The only time he was relatable was when he was actually playing."

At least twice, he was committed to treatment centers -- via the Baker Act, under which psychiatrists may deem a person "dangerous to self."

Back on the street, his mental condition was inflamed by a lack of steady music employment. He was one of the best bass players alive. Everyone had told him that for years. But no one would hire him.

SOMETHING WAS WRONG

By the summer of 1985, he knew, at least in the back of his mind, that something was wrong. Musicians looked for him in the park just to gawk. He was often filthy, reduced to begging on the street for food. During an interview in Washington Square Park that August, Pastorius cried as he spoke of his desire to return to Florida and reunite with his four children. "I just want to go home. My best friends in the world are in Florida. My children are in Florida."

Diagnosed as an alcoholic and a manic depressive, he spent four months at Bellevue in the summer of 1986.

The bassist did return to Florida in late December 1986 but continued to live without much apparent concern for his music, family or basic creature comforts. Many, like his longtime friend and instrument repairman Kevin Kaufman, tried to help him. One way or another, he blocked those with the best intentions, including his ex-wife Ingrid.

"It's been a long stretch of sadness," she said last week. "But I always felt he was playing out a need that was uniquely his. He was fulfilling something in himself that no one else can understand, because it comes from his isolated personal experience, coming into the world and being one of the most talented people in the music business. I've tried to maintain a respect for him -- he is the same man who has shown such incredible beauty to so many people."

Said Kaufman: "I let him stay here for a few weeks, but it got to be too much trouble. He was every bit as bizarre six years ago, but now the lucid moments were few and far between."

According to Kaufman and others, Pastorius made several attempts to concentrate on music, but each one ended in a drinking binge. He was regularly thrown out of nightclubs. He gave away his bass in the West Palm Beach ghetto. Once he fell asleep on the railroad tracks between Deerfield Beach and Pompano Beach.

It wasn't so much the incidents that scared people. It was his attitude. "It didn't bother him in the least that he had passed out on the railroad tracks," Kaufman said.

"It's seemingly a self-destruction thing," said guitarist Randy Bernsen, a longtime musical associate. "He's almost saying, 'How much can I hurt myself?' "

Pastorius laughed at that idea earlier this year in Holiday Park: "People are running around saying I'm self-destructive and shit. I'm not self-destructive. I am not an alcoholic; I am not a drug addict; I am a party-er. I take chances."

EXPLORING THE EDGE

To students of music, Pastorius' words have a familiar ring. He is the latest in a procession of tortured geniuses stretching from Mozart to Billie Holiday, Jimi Hendrix and, perhaps most directly, the mercurial alto saxophonist Charlie Parker.

Like Parker, the lanky, animated Pastorius has made up his own rules of conduct -- both on and off the bandstand.

Like Parker, an intermittent heroin addict who died of liver failure in 1955 at age 34, he has had problems controlling his dependency on addictive substances -- once cocaine, more recently alcohol.

Like Parker, he was an innovator, the beacon for a generation of bassists and the architect of a looser, R&B- influenced kind of groove that soon swept the music.

Like Parker, his musical presence -- the energy with which he delivered his elastic phrases -- was unmistakable.

But unlike Parker, Pastorius' innovations have been subtle, not earth-shattering. Though gifted with an unswayable -- and instantly identifiable -- sense of time, Pastorius didn't hammer out the pulse in the repetitive manner employed by most bassists. Instead, he approached the role of the bassist soloistically, creating elaborate phrases that suggested not only tempo, but melody as well. Even his supporting lines, the stock in trade for a bass player, were thoughtfully crafted, liquid-sounding gems of improvisation.

'RARE AND IMPULSIVE'

"Jaco is one of those rare impulsive musicians," Joni Mitchell said in a 1985 interview, recalling her long working relationship with the bassist. "Even if what he was doing seemed crazy, you went with it just to see what would happen. He really made the Mingus album come alive that way."

"It almost seemed electrical when we played," said Bullock, a New York-based guitarist who worked with Pastorius in a trio setting he describes as the "Cream of the '80s" throughout late '85 and early '86. It was Jaco's last professional situation, a band led by Bullock but built -- and booked -- on Pastorius' notoriety.

"The guy is/was a true genius on the level of Mozart or Beethoven. He'd be fine, we'd do rehearsals with this heavy music and things would go great. Then to play the gig, the intensity of the energy was too much for him. It was an unequilibrizing thing. He has to learn how to deal with that energy in a nondestructive way."

SPECIAL FROM THE START

For the period when his career was rolling, Jaco Pastorius was able to channel that energy into stunningly fresh artistic channels.

A musical child, he developed into a bassist of substantial originality by the time he finished at Northeast High School in Fort Lauderdale. Though he was largely self-taught, he took some classes at the University of Miami and soon wound up giving bass lessons there. His classmates included Bullock, guitarists Pat Metheny and Steve Morse, pianist Mike Gerber.

In 1976, he was hired by Joe Zawinul and Wayne Shorter to join Weather Report. His first contribution was to the popular Heavy Weather album, which contained the pulsating hit Birdland and Pastorius' infectious Teen Town.

For the next five years, with breaks for various projects in between, Pastorius helped guide Weather Report to a new plateau of interactive fusion. With Zawinul shifting the focus between highly orchestrated melodies and free improvisation and Pastorius pushing the rhythm section to a relentless series of peaks, the band sounded like a churning juggernaut at warp speed. No other product of the fusion era quite had the impact of Weather Report -- particularly during the Pastorius era, which ended when he left the group in 1982.

The raves came quickly for Pastorius. He zoomed to the top of polls conducted by magazines such as down beat and Guitar Player. On Pastorius' first solo album, Herbie Hancock, not one prone to overstatement, called him "a phenomenon." That album and the next one, Word of Mouth, were both nominated for Grammies.

While bassists all over the world were scratching their heads over Jaco's awe-inspiring technique, arrangers were studying his albums for the writing -- which featured an updated, breezy approach to the big-band horn section. Local bandleader Peter Graves, whose band accompanied Pastorius on the Word of Mouth tour, said recently "every time I turn on Y-100 I hear how he reshaped the world of the bass. But as important as his playing is, I believe his pen was mightier than his bass. His writing is just on a different plane."

MANIC ENERGY

Following Jaco's stint at Bellevue, Gregory Pastorius began to believe his brother's manic energy was essential to his music.

"They were giving him a drug called Tegretol, and it seemed to make him quite a bit different. There was one big negative side effect -- he couldn't play on it. He was so used to being up on that edge, that when the drugs slowed him down, he didn't feel that same internal punch. It definitely affected his music."

Gregory and others agree that even this year, as Jaco's problems began to multiply, he still had the ability to play music.

Instrument repairman Kaufman recalls Jaco wrestling with his gloried past earlier this year: "One time, and only once, I heard him say something about having done it all. He said, 'I can't equal that.' I don't know whether he believed it or not."

"I heard something change about a year ago," Gregory said. "He started playing the same things over and over. You know, in his solo, America and Third Stone From the Sun every night. There were no new ideas. But he was still playing."

Bernsen remembers a guitar/bass duet with Jaco at the Musicians Exchange earlier this year. "We played Blackbird, some other Beatles' stuff. The music was unbelievable . . . He was remembering the (songs) we did 16 years ago, stuff I didn't remember."

NEW MUSIC

Bernsen said Pastorius came by the studio when he was released from jail last week, interrupting a session to play him a new composition on the piano. "It was beautiful," he said.

Though he's been known to call up record company executives at odd hours, Pastorius has still been able to generate some interest in his projects. Ricky Schultz, now president of MCA Records' jazz division, was responsible for signing the bassist to Warner Brothers Records in 1981. One of the few people Pastorius trusts in the business, Schultz has tried more than once in the past year to secure a contract for Jaco's unreleased Holiday For Pans album and other projects.

Schultz believes that "the thing that's really eating him up is the fact that he's sitting on the sidelines not making music. It's working on him like a cancer."

Fans have seen this side of him time and time again: Pastorius is known for joining touring artists onstage for impromptu jam sessions. He was welcome when he bolted onto the stage at the James L. Knight Center in 1984 in the middle of a Weather Report concert. Cheers broke out when he emerged from the audience to play with Mark Egan during a Michael Franks show at New York's Avery Fisher Hall in 1985.

But last week, when he jumped onstage at the Sunrise Musical Theatre during Carlos Santana's show, it was a different story. After a brief altercation, Pastorius was escorted out by security, without being asked to play.

Five hours later, he was face down in a pool of blood on a Wilton Manors sidewalk. According to the police report, he tried to enter the private Midnight bottle club and encountered an unfriendly manager, who told police Pastorius fell after attempting to punch him. On Friday, police charged the manager with aggravated battery.

Pastorius has a fractured skull, fractured facial bones and pneumonia. Although still in a coma, he is responding to simple commands. But doctors remain unsure whether he will regain the use of his right eye and left arm.

"There are some heavy things going on with him right now," Bernsen said. "It's up to his will to live. If he was playing with the idea of self-destruction, it'll come to a test now. Anything the cat does -- music or anything else -- it's huge. This is no exception."

This time, he said, "It's all or nothing."

CORRECTION:
A story about bassist Jaco Pastorius in Sunday's Lively Arts section misstated his first involvement with Weather Report. Pastorius played on parts of the 1976 album Black Market. He made a more significant contribution to the 1977 release, Heavy Weather.