Sugar Ray Leonard and Muhammad Ali have more in common than a flamboyant style in the prize ring. They both have the aching fists common to many boxers, but anti-inflammatory agents can ease the swelling and discomfort of their arthritic knuckles, enabling them to continue in the trade they ply so artfully.

Dennis Maruk of the Washington Capitals suffered a hyperextended elbow in a hockey game in Denver last winter. That is a euphemism, meaning his arm was bent back in the wrong direction from the elbow. The next day, Maruk had his arm in a sling, but he did not miss a game. Treated with anti-inflammatories to reduce swelling and oral analgesics to relieve pain, he was able to play.

Golf is one of the more sedate professional sports, but Lee Elder of Washington needs to have his knee drained of fluid and injected with cortisone at least once a year in order to keep an old sandlot football injury from acting up and making it uncomfortable for him to walk 18 holes.

Most discussions of drugs in sports focus on what is generally referred to as "doping" - athletes using chemical substances, often surreptitiously and in violation of the rules, to try to improve their performance beyond the levels of which they would normally be capable.

But there is another realm of drug use in the sports world. It involves the use of legitimate medications for treatment of injury or illness that would otherwise keep an athlete on the sidelines, or prevent him from performing anywhere near his normal capacities.

"People should understand the differences between using therapeutic medications to treat athletes, and using drugs to enhance performance. They are two separate subjects, and should not be discussed together," said Dr. Robert Kerlan, a respected Los Angeles orthopedist.With six associates, he operates the Southwest Orthopedic Medical Group, which attends to the medical needs of the Los Angeles Dodgers and California Angels in baseball, the football Rams, hockey Kings, basketball Lakers and several college and high school athletic programs.

There is a great potential for abuse of legitimate medications. The most controversial of the drugs the sports doctor has at his disposal are local anesthetics, usually referred to less specifically as "painkillers."

Consider these tales of athletes and their diverse experiences with local anesthetics:

Sandy Koufax was scheduled to pitch for the Los Angeles Dodgers against the New York Yankees in the fourth game of the 1963 World Series. But the day before the game, the peerless left-hander had an infected toenail so painful that he fiddled with it until he finally pulled it off. The day he was scheduled to pitch, the toe was so tender, Koufax could barely walk.

Dr. Kerlan, the Dodger team physician, examined him and decided that if the pain could be blocked, and the toe properly wrapped and treated to avoid further infection, Koufax could pitch without risk of aggravating his condition.

"In this case, I blocked his toe (eliminated the pain) by giving him an injection of a local anesthetic, a procedure I use only raredy and in carefully selected circumstances," recalled Dr. Kerlan. "I stayed in the dressing room, ready to give him an- other injection when the first wore off. But he dispatched the Yankees so quickly that we didn't have to reblock it. He won the game, 2-1, to clinch the series, and his toe and arm were fine."

Bob Gross, a forward for the National Basketball Associateion Portland Trial Blazers, was disturbed when his left ankle "just started hurting one day" during the 1977-78 season. He couldn't remember injuring it, but it ached.

Whirlpool, heat treatments and other routine therapy did not seem to help it. Team physician Dr. Robert Cook diagnosed the problem as tendinitis, a common ailment among athletes, but surprisingly did not X-ray Gross foot.

Despite treatments, the ankle continued to throb. "It got to the point where I couldn't play," said Gross.

On March 18, 1978, Gross took an jection of the local anesthetic Xylocaine (lidonaine) similar to Novocain, but longer-lasting - direftly into the souree of his pain. "It worked right away and killed the pain for two hours, long enough to play the game," Gross says. "After the shot wore off, it didn't hurt any more than it did before."

But the ankle continued to be too painful for him to practice. On March 21, he needed three shots of Xylocaine - one before the game, another at halftime, and the third in the third quarter - to play a game in Seattle.

Two nights later, before another relatively meaningless regular-season game in Milwaukee, the ankle was more painful than ever, so Gross took an injection of Marcaine (bupivacaine), another local anesthetic that is stronger than Novocain or Xylocaine and deadens sensation for a longer duration, up to 20 hours.

During the game that night, Gross suffered a stress fracture of the ankle. "I didn't feel a thing; I wouldn't have known I broke it except that I heard it snap," he said.

Now, more than a year later, Gross still is having problems with the ankle, and at 25 his career may be in jeopardy. But he refuses to second-guess his decision to take painkilling injections.

"I wanted to play," he said. "I always want to play." He thinks his big mistake was not insisting on having his ankle X-rayed to determine if there was something more wrong with it than tendinitis.

Dr. Cook was not available to comment yesterday on Gross' case. In a Sports Illustrated article last August, Cook acknowledged that it was rare for him to prescribe medication without first taking an X-ray of an injury.

A spokesman for the Trail Blazers said yesterday that at the time Gross was hurt, "We were trying to post the greatest record in NBA history and there may have been subtle pressure for players to play hurt. There has been a definite change in procedure this year, however. We almost wouldn't let a guy play if he was hurt at all. Maybe we overreacted a bit."

Late in the first week of Wimbledon in 1976, Sweden's young tennis star, Bjorn Borg, pulled a muscle in his lower abdomen in a doubles match. At first, he thought it was a minor injury, but it became increasingly painful. Borg's coach, Lennart Bergelin, took him to a doctor, who diagnosed the ailment as a tear of the rectus abdominus, a muscle that is stretched repeatedly as a tennis player reaches high to serve or hit an overhead smadh.

Borg apologized to his partner, Guillermo Vilas, and defaulted from the doubles. He said publicly that he probably would have to drop out of the singles as well. But the next day, he went on court and walloped Brian Gottfried, 6-2, 6-2, 7-5, to reach the quarterfinals.

Borg explained to skeptical reporters afterwards that he had taken an injection of Xylocaine in his lower stomach shortly before the match, and was concerned with winning quickly, before the effects of the painkiller wore off.

Borg continued to say the same thing throughout the following week as he annihilated Vilas, 6-3, 6-0, 6-2; Roscoe Tanner, 6-4, 9-8, 6-4, and Ilie Nastase, 6-4, 6-2, 9-7, to winthe first of three consecutive singles titles.

Before each match, he took another injection, and during changes of ends he sat on his chair, lifted his shirt, and sprayed himself with ethyl chloride, the aerosol "freeze spray" that trainers in American pro sports regularly trot out with to treat a baseball player who has fouled a ball off his shin, or a basketball player who has jammed a finger.

The following week, Borg Defaulted from a Davis Cup series, leaving Sweden defenseless in its attempt to keep the international trophy that he had slmost singlehandedly captured the previous year. He really did have a torn stomach muscle, and had aggravated it while playing number by local anesthesia. In all, he sat out for seven weeks, letting the muscle heal naturally. He returned to action the last week in August, one tournament beofre the U.S. Open.

Most aholetes regard pain as their public enemy no. 1.

Palin is not the real eneny, of course. It is merely a sypmton, a message that there is something wrong in a joint, a muscle, a tissue, a tendon, an organ or some other component of the body.

Athletes frequently are given analgesics for relief of the pain of bumps, bruises and chronically annoying ailments.

Occasionally, though, athlestes are given injections of a local anesthetic. This is a much more serious and precarious business fro, unlike the analgesic that relieves pain without totally blocing it, local anesthetics eliminate all sensation, including the pain that would alert the athlete if he were doing grave damage to himself.

There are many types of injuries - such as Koufax's - in which the risk of doing further damage by playing on them without sensation is minimal. In these cases, use of local anesthetics to enable an athlete to play may be medically justified and prudent.

The vast majority of athletes, for a variety of personal and cultural reasons, choose to "play hurt" if they can play at all.

=I've taken shots to reduce or kill pain in order to play, and I've never done it on anybody's instuctions but my own, for reasons that were my own. I felt my place was on the field, helping the team, playing to my best capacity," said former Washington Redskin Center Len Hauss.

"I played the last six games of the 1977 season with three broken ribs. I'll be honest with you and tell you I didn't do it on guts alone. I had some.And I had to get in line to get my injections."

Hauss said that in his 14 NFL seaons, he never was given a shot without having all the risks explained, and that the final decision was invari- ably his. He thinks this is the norm throughout pro football.

"We handle a heck of a lot of grievances through the players' association, and I have never heard anybody say he was made to take a painkiller he didn't want," said Hauss, one of three members of the NFL Players Association Safety and Welfare Committee. "If there was such a problem, that is where we'd hear about it, so I'm certain that any use of painkillers is up to the individual."

A criticall question is, how much of a responsibility does the team physician have to "protect the athlete from himself."

Dr. Stanford Lavine, the orthopedist who is team physician for the Redskins and Washington Bullets, believes that his only obligation is to spell out the risks thoroughly. Then if a player wants to compete, it is his choice.

"Jake Scott (veteran Redskin free safety, recently waived) played last year with four broken ribs," recalled Lavine. "I explained all the risks, made sure that he understood what he could do to himself, but he wanted to play, anyway. He was very definite about it.

Lavine said he is not worried about malpractice suits because "I practice good medicine." But in cases such as Scott's, he noted, he is cautious enough to have witnesses in the office when he explains the possibilities.

"These players are adults. They're over 21, and they can decide for themselves what they want to do," said Lavine. "With college athletes, it's different. (Lavine also is the physician for the University of Maryland teams.) We make decisions for them. But with the pros, we leave it up to them what to do with their bodies."

Said Dr. Eugene Brusky, a general practioner who had been team physician for the Green Bay Packers since 1962; "There definitely is a lot of pressure put on the team physician and trainer to get a player ready quickly, especially if he's a star player and you're going into a big game.

"But the player is always given options. I've always made it a point to explain what could happen, and he decides . . . Ninety-nine times out of 100, he'll decide to play.

"That is, in cases where there is minimal risk. If there's a big risk, we won't let him play, period. Nobody is sent out with a weight-bearing joint deadened by local anesthetics, for example. But if a fellow has a broken hand or a cracked rib or something like that, and you can adequately protect it and ease his pain, he's pretty much expected to play.

"A lot of people saw Bert Jones (Baltimore Colts quarterback) playing last year with his separated AC (the acromio-clavicular joint, between the shoulder and collarbone). He was obviously in pain, but there was little prospect that he could do any more damage to the joint. I don't frown on that at all. I think a guy who is getting $125,000 a year should play with some hurts.

"Of course, you do run into a breed of player nowadays that you just can't get to play with any type of injury. These people are generally weeded out in a hurry, at least as far as our ballclub is concerned."

Mike Thomas, the talented running back recently traded to San Diego by the Redskins, is an example. Last season, he refused to play on a sore ankle that some team officials and players did not consider serious enough to keep him sidelined. Thomas did not want any injections.

"After the shot had worn off, how bad would my ankle have been then?" he said. "It was already injured. You can't go out and play and expect it to get better."

And then there's Bill Walton, Considered by many to be the most dominating player in the NBA when he is healthy, Walton demanded to be traded from his once-happy home in Portland because of disenchantment with what he considers the Trail Blazers' excessive use of local anesthetics and anti-inflammatory agents that can have adverse effects.

Not long after Gross suffered his stress fracture in 1978, Walton was urged by the Blazers to take a pain-killing injection so that he could play on a gimpy left foot.

After resiting until the playoffs had begun, Walton reluctantly took a shot of Xylocaine. No one forced him to, but it was made abundantly clear to Walton that his teammates and coach, not to mention the team trainer and physician (both close friends), felt it was imperative for him to play if the Blazers were to have any chance of defending their @NBA title.

Walton took the shot and played. After the next game, x-rays revealed a broken bone beneath his left ankle. That was more than a year ago, and Walton has not played another game since. Incensed with what he considered irresponsible use of medications that led to aggravation of his injury, he demanded before the 1978-79 season to be traded. He sat out the year and eventually signed with San Diego as a free agent.

Last month, speaking at Stanford University, Walton said, "I don't blame Dr. Cook. I blame myself. I made the decision to take the shots."

The Blazer spokesman, asked about the team's handling of Gross and Walton, said simply, "They were medical decisions. Dr. Cook is still our physician."

Also at issue with the Trail Blazers is alleged overuse of the antiinflammatory agents Decadron (dexamethasone) and Butazolidin (phenylbutazone), both of which can have adverse side effects.

One Trail Blazer player told Sport Illustrated that all a player had to do was request Decadron or Butazolidin, and it would appear in his locker shortly thereafter. The medicine cabinet containing prescription drugs was allegedly left unlocked, contrary to league rules.

In the same Sports Illustrated article, Ron Culp, the Blazer trainer, said that he only gives medication to a player whose condition Cook knows about, and that he carefully records the administration of every pill, in accord with NBA rules.

The control of abuses ultimately lies mostly with the trainers and physicians. What are their priorities? The short-term goal of getting an injured player into the lineup, or concern with his long-range health and safety?

"Often I've had a player say before a game, 'Can't you do something for this pain or this soreness?' When athletes ask for something to help keep them playing, we say 'No' more often than 'Yes', said Dr. Kerlan. "We say 'No' because it's against the player's short and long-term interest. What's the use of helping him play another half at the cost of missing the next three or four games?"

Next: Some possible solutions. CAPTION: Picture 1, Sandy Koufax; Picture 2, Mike Thomas