In the wake of Pete Rose's expulsion from baseball for betting and George Steinbrenner's admission that he gave $40,000 to a gambler, sports and law enforcement officials say they are concerned about the growing influence of gambling on college and professional leagues.

While a sporting event being fixed remains their greatest fear, league officials say they are grappling with a more everyday concern: that gamblers and bookmakers -- some with ties to organized crime families -- are approaching athletes to gather information that would be useful in formulating bets and odds.

"Gamblers are more aggressive now," said Kevin Hallinan, security director of Major League Baseball. "They're trying to get closer to the athletes and to people who work within the game. I'm very much concerned about that trend. . . . It is a very scary thing."

In some instances, unwitting celebrities have been used to gain access to major league players and umpires, Hallinan said. One gambler lured a player to a party by telling him a celebrity wanted to meet him, and in other instances players have received gifts from gambling figures, he said.

"It's called the edge," Hallinan said of the gamblers' motives. "And the edge is that little piece of information from somebody inside that locker room, be it a player, a clubhouse guy, an umpire. Gamblers believe that, no matter how small the information, that edge is going to put them over the top."

"Gamblers aren't only interested in injuries or learning the game plan," said Warren Welsh, the National Football League's security director. "They want to know if a player has financial woes or family problems because these can have an adverse influence on a player's performance."

Pro and college sports personnel are forbidden by their leagues from associating with gamblers and from betting on their respective sports. While gambling has long cast a shadow over the sports world, the last 12 months have been notably dark.

In baseball, former Cincinnati Reds manager Rose placed bets -- directly or through intermediaries -- with bookmakers who had ties to organized crime families in Illinois, Massachusetts and New York, according to Hallinan. In basketball, former North Carolina State star Charles Shackleford has been accused in a report on ABC-TV of fixing games, an accusation he has denied. In football, former athletes at Texas, Arkansas, Florida and Mississippi State have been investigated for alleged gambling activities.

Meanwhile, Steinbrenner, the New York Yankees' principal owner, said he paid admitted gambler Howard Spira to keep him from revealing damaging information about former club employees. Spira said he accepted $40,000 from Steinbrenner in return for detrimental information about outfielder Dave Winfield. Baseball Commissioner Fay Vincent is investigating. Big Business, Big Money

Sports gambling is a flourishing business. In Nevada, $1.35 billion was wagered legally on sports during the last fiscal year, and sources say as much as $100 billion is bet illegally in the United States each year. With more money than ever at stake, gamblers and bookmakers have become increasingly adept at gathering information about athletes and teams, according to league and law enforcement officials.

"The bookmaker knows more about some teams than some of the coaches do when they prepare for another team," said Tom French, an FBI supervisory agent who works closely with college and pro teams. "The bookmaker has a network. He can pick up the phone and if he needs to know what's going on in a locker room, he has somebody who can find out. Whether it's a ballplayer who has a marital problem or narcotics problem, these are all factored into the line."

Hallinan and Welsh said gamblers have long attempted to contact athletes at bars and restaurants. "But now the approaches are more sophisticated," Welsh said. Gamblers are "going into the nicer restaurants and nicer clubs, engaging athletes in conversations, buying them drinks, buying them dinner, doing favors for their girlfriends and wives."

When he became baseball's security director in 1986, after 25 years with the New York City Police Department, Hallinan said he was surprised by the "numbers of people that were trying to infiltrate professional baseball and professional sports" and by the "tactics they used to try to get close to athletes."

In the last several years, Hallinan said, gamblers and bookmakers have used unwitting movie stars, television personalities, professional wrestlers and country and western recording artists to establish relationships with players and umpires.

After relationships were forged, gamblers and bookmakers invited the players and umpires to dinner, even sent gifts to their children, Hallinan said. Most of these gambling figures have ties to organized crime families, he said.

Typically, the athletes and umpires were questioned about injuries and players' personal lives. "Some pretty far-out questions have been asked," Hallinan said, declining to name the athletes and umpires he said have been approached.

Professional teams issue regular injury reports, partly to minimize the amount of so-called inside information available to gamblers. But inside information still is available because players do not report all of their ailments and injuries to trainers and coaches, league officials said.

"You're looking at things like sore arms," Hallinan said. "Or a guy's got a pulled muscle. He doesn't want to come out of the lineup. He's starting to go downhill. His average is starting to drop. So nobody knows {about the ailment}. He's keeping it a secret."

"You just have a lot of players that are just very, very competitive, and they're going to play with a great deal of pain," Welsh said. "And sometimes those players playing in pain just aren't quite as effective as a well player would be. That's not always going to come out on an injury report, but that information certainly would be a key to somebody that's gambling on the game."

At the college level, player injuries are not routinely announced by football and basketball teams. But college injuries rarely remain hidden from gamblers, according to Michael Roxborough, a Las Vegas oddsmaker.

Roxborough said he often phones reporters to gather information on college teams. "If I need to find out about injuries, beat writers are the best to call," he said. "Sometimes I tip them off to stories they don't know, so I'm doing them a favor too."

Rich Levin, public relations director for Major League Baseball, said some reporters are betting on games they cover. "It goes on a lot . . . reporters talk about bets they've made, how much money they've won or lost," he said. "And on occasion {they} call from a press box phone to a bookmaker."

Last year the baseball commissioner's office took the unusual step of revoking the credentials of two news media representatives who were observed gathering information in clubhouses, then using stadium phones to place bets, Hallinan said.

"We caught them in the act {at ballparks}, putting their action in," he said. "They were extremely embarrassed about it. . . . They said they just got carried away." Hallinan declined to name the reporters or specify whether they are employed in the print or broadcast media.

Chet Forte, a former director of ABC-TV's "Monday Night Football," recently admitted having an addiction to sports gambling. NBC Sports executive producer Terry O'Neil said in his book, "The Game Behind the Game," that he once observed Forte phoning a bookmaker from the ABC director's truck. Biggest Worry: The Fix

Nothing worries league security officials more than the threat of a fix. Dozens of college basketball games were fixed during the 1950s and '60s. In 1981 a Boston College basketball player was convicted for his role in a point-shaving plot that was backed by the Lucchese crime family. In 1985 several Tulane basketball players and students pleaded guilty to participating in a point-shaving scheme.

In February ABC-TV reported that an alleged New Jersey gambler, Robert Kramer III, paid Shackleford and three unnamed former North Carolina State basketball players to shave points in as many as four games during the 1987-88 season. Kramer and Shackleford have denied the allegations, which reportedly are being examined by a New Jersey grand jury and the North Carolina State Bureau of Investigation.

Scott Schettler, who directs one of Las Vegas's largest betting operations, the Stardust Hotel Race and Sports Book, said he doubts a fix occurred because no unordinary amount of money was bet on the suspected games. "We would know if something's wrong," he said. "There was nothing wrong. It's as simple as that."

Shackleford is now a forward with the National Basketball Association's New Jersey Nets.

NBA Senior Vice President and General Counsel Gary Bettman said his league isn't particularly worried about fix attempts. "Relative to what our players make, I don't know that there's enough money that could cause one of our players to fix a game," he said.

But some sports and law enforcement officials said soaring salaries do not eliminate the possibility of a fix, especially in view of increased drug and gambling activity in the United States.

"The worst-case scenario is that an athlete who's a drug abuser becomes indebted to his drug source and can't pay," said Welsh, a former FBI agent. "The athlete then gets that little knock on the door at 2 some morning, and he's told: 'Now you have two employers. One may be your football team but the other is us.' "

"The biggest {gambling} concern of the FBI and probably all the professional and college leagues is the potential use of bribery or extortion to compromise an athlete," French said. "Three areas we concentrate on are money, narcotics and women. These are the areas we feel an athlete could be most vulnerable."

People in the Las Vegas gambling community disdain talk of fixes or organized-crime involvement in their business. "The crap about bookmakers breaking people's legs if they don't pay, that's all bull," said Billy Walters, a self-described high-stakes bettor and former bookmaker. "That might have happened 20 years ago. But it hasn't happened in the last 20 years that I've been involved."

Some federal law enforcement officials disagree, and they point to recent court cases. In December 1988, for example, an alleged associate of the Genovese and Gambino organized crime families, Vincent Matturro of Scarsdale, N.Y., was arrested on charges he operated a multimillion-dollar football betting ring. Several days later Matturro was found dead, hanging from a rope in the garage of his home.

Last year, the alleged leaders of a New York sports gambling and loansharking operation were indicted on charges they threatened bodily harm to bettors who didn't repay loans. A representative of the defendants set fire to one man's car and threatened to break another's legs, the indictment alleges.

Welsh said organized-crime figures have attempted to make inroads with NFL players in "very limited situations." NBA security director Horace Balmer declined to be interviewed for this story, referring all questions to Bettman. Asked about possible ties between gamblers and NBA club and league personnel, Bettman said: "I don't want to comment. . . . The whole issue is sensitive. I don't want to fuel speculation. . . . We have not had any gambling problems, and we're proud of that."

In the aftermath of the Pete Rose scandal, leagues have taken steps to distance themselves from gambling. "The leagues realize gambling has the potential to destroy the golden goose," French said. "Once the public's confidence is shaken by a scandal or two, the game could go down the tubes."

Vincent flexed his muscles in Washington recently, warning that a proposed sports lottery game could reduce the city's chances of getting an expansion franchise. Several days after Vincent's statement the D.C. Council voted to block creation of a sports lottery game.

After learning Rose had placed bets from ballparks, Vincent ordered clubs to log phone calls to and from clubhouses and umpires' locker rooms. Earlier, the commissioner's office barred nonessential personnel from clubhouses. "Once you get burned, you start closing the doors," Hallinan explained.

The NBA has filed suit against the organizers of a state sports lottery in Oregon. "Our players have been on record as saying they don't want to be bet on like horses," Bettman said. And the NFL has notified five television networks it does not want gambling-oriented information on game-day telecasts. Welsh said the TV betting segments created a perception that "the NFL condoned betting."

One apparent double standard remains: While NFL players are forbidden from betting on games, even in Las Vegas, the league allows hotel owner Barron Hilton, whose Las Vegas Hilton houses a sprawling sports bookmaking operation, to remain a minority owner of the San Diego Chargers. Welsh said NFL Commissioner Paul Tagliabue will review Hilton's ownership status. Plenty of Warnings

Athletes and club officials can't plead ignorance to the subject of gambling. Since 1982 FBI agents have been making annual visits to college and pro teams, warning them of the pitfalls of this activity.

FBI agents have warned players repeatedly since the mid-1980s that a woman, posing as a fashion model or portrait artist, has lured dozens of college and pro athletes to hotel rooms and, in some instances, drugged and photographed them in compromising positions, according to law enforcement sources.

Based on an unrelated case, a federal warrant has been issued in Cleveland for the arrest of a man who has assisted the woman and who allegedly has sodomized an athlete, sources said.

"They're hoping to blackmail athletes, trying to gain some benefits from them down the road," said Frank Torpey, security director of the National Hockey League. "The most likely benefits would be to obtain inside information on teams or to eventually alter the outcome of a game."

"We're certainly aware of it, and {NFL} players' names have come up," Welsh said. "They had lists of people that were on their kind of hit list. Most of these scams seem to be aimed at getting money from a person. But there's no reason it couldn't be used -- attempted, at least -- to influence the outcome of a contest."

Some associations between sports and alleged gambling figures seem inevitable. For example, two newspapers and a Detroit television station reported in June that a close friend of Pistons guard Isiah Thomas is a target in an FBI gambling investigation. The friend, Imad Denha, is a former next-door neighbor of Thomas and the godfather of Thomas's son, Joshua. Thomas is not a suspect in the case.

Nevada-Las Vegas's NCAA championship basketball players can scarcely visit a fast-food restaurant without meeting a gambler. Not only is sports gambling legal in Las Vegas, some of UNLV's most prominent boosters, including Steve Wynn, owner of the Mirage and Golden Nugget hotels, operate legal sports books.

"If the kids are betting and stuff like that, you know, that's bad," UNLV Coach Jerry Tarkanian said. "But to go out and have dinner with a guy who works in a casino, what the hell. That's his livelihood. There's nothing wrong with that."

One gambler who seemed harmless to Tarkanian was Sam Perry, a New York summer-league coach who gambled in Las Vegas. Perry helped support one Runnin' Rebels recruit, befriended at least two others, and was seen in 1987 around the UNLV basketball coaches' offices.

UNLV players later learned that Sam Perry was really Richard Perry, a twice-convicted sports fixer. "We don't encourage our athletes to interact with people with unsavory backgrounds," UNLV Athletic Director Brad Rothermel said recently. "But how do you prevent it? You know, it's virtually impossible to follow 15 student-athletes every hour of the day."

The NFL won't soon forget its own "Pete Rose": former Baltimore and Indianapolis Colts quarterback Art Schlichter, who was suspended by the league in 1983 after he reportedly piled up $750,000 in gambling debts. Schlichter underwent treatment for a gambling addiction and was arrested on illegal gambling charges four years later.

Schlichter, who entered another treatment center last fall, now quarterbacks the Detroit Drive of the Arena Football league. At 30, he said he dreams of returning to the NFL. This spring he was observed betting on sporting events in Las Vegas hotels, according to Welsh and Nevada gambling sources.

"Somebody said if you're ever looking for Art Schlichter, all you have to do is go to the Stardust," Welsh said. "With no mask or anything else, I guess he was just hanging out there. Art's had his problems." Schlichter could not be reached for comment. Illustrating a Point

This fall, FBI agents will return to NFL training camps for their annual lectures. French, who has spoken to dozens of pro teams, from baseball's Los Angeles Dodgers to football's Washington Redskins, said he'll warn players of the federal penalties for fixing games and of the scams being attempted by gamblers.

"When we go into the specifics of different {scams}, it seems to ring a bell with the athletes," French said. "The light goes off in their heads. They say, 'Geez, I remember that happening when I was on the road in Detroit or Cleveland or Buffalo. . . . "

For those who cannot relate, or who believe his lecture is much ado about nothing, French will display a newspaper clipping that appeared the day after Rose was banned from baseball. "I think the headline sends a pretty strong message," French said.

The headline reads: