It was but a few sports seasons and athlete attacks ago that a staff member of the Association of Tennis Professionals jokingly gave himself a “Double 0” number. He was negotiating with an international security agency to see what steps should be taken to beef up protection on the tour. “It seemed almost funny back then,” he said. Now in a span of less than nine months: Monica Seles knifed in the back on a tennis court in Hamburg…Nancy Kerrigan assaulted at an ice rink in Detroit. And the less vulnerable men? Heavyweight champions Evander Holyfield and Riddick Bowe dive-bombed in the boxing ring by a paraglider in Las Vegas…U.S. Olympic luge-team member Duncan Kennedy gang-attacked in Oberhof, Germany…Washington Bullet Larry Stewart burglarized and shot in suburban D.C. barely hours after the Kerrigan attack. Nobody is laughing anymore. Nor does any athlete seem safe because he or she is an athlete. Who they are may be the reason why they aren’t safe. “We’re going on the assumption that this is not a trend,” says the tennis fellow, who’d rather not be identified lest he be targeted by some head case, “but…”

Violence toward high-profile athletes isn’t exactly New Age. Sports was traumatized forever in that most frightening of Olympic moments in 1972 when Black September terrorists invaded the Olympic Village in Munich and took Israeli athletes hostage. In the end, 11 members of the Israeli team died. That attack used sports as a convenient venue for political murder. Since then the Games have become acutely security-conscious, and violence has become the work of apolitical crazies.

Seles was the victim of an unemployed German lathe operator who wanted to injure her so that Steffi Graf could become No. 1–which Graf did. Meanwhile Seles, inactive since the stabbing last April, fell to number eight. Last week she announced she would be unable to defend her title at the Australian Open. And she broke her public silence to reach out to her new partner in an unhappy, unsought sisterhood. “Nancy is an ice skater. I’m a tennis player,” Seles said last week. “Crimes against us are no more tragic than what happens to too many innocent victims every day…My hope is that this kind of terrible incident will focus…to stop senseless violence against innocent victims.”

Of course, SVAIV (senseless violence against, etc.) has become a pastime as American as the American pastime itself. In 1949 Ruth Ann Steinhagen opened a Chicago hotel door and shot Philadelphia Phillies first baseman Eddie Waitkus with a .22 rifle. In 1986 California Angels’ first baseman Wally Joyner was hit by a knife thrown from the upper deck of Yankee Stadium. “There’s quite a few gooney birds out there,” Joyner says. “It’s what makes sports so great.”

The very night of the Seles incident, four gooney birds rambled onto Cleveland’s Municipal Stadium diamond–one shook Indians outfielder Albert Belle’s hand, another slid headfirst onto home plate–and after making sports so great were promptly arrested. Luckily, the Oakland As were at bat. “They get close to me, I’ll kill ’em,” reportedly said A’s outfielder Ruben Sierra. Which is almost what Baltimore Colts linebacker Mike Curtis did to that silly fellow who ran onto the field in a famous incident in 1971.

What happened to the sanctity of sports celebrity? What happened to the bubble of safety encircling our athletic stars? Well: (a) Macho drunks tested our heroes. “I represent 23 NFL quarterbacks,” says Leigh Steinberg, the California sports attorney, “and we counsel them: ‘If you can’t walk away (from insulting situations), don’t walk out in public at all’.” (b) Aggressive collectors encouraged a rougher type of interaction. The sheepish fan asking longingly for an autograph has been replaced by the leering collector thrusting a ball in someone’s face and trying to Pull his wristwatch off at the same time. (c) Disturbed romantics wrote letters, made phone calls, obsessed, obsessed, obsessed. Steinberg tells of a weird woman sleeping in her car in front of a quarterback’s house, then screaming hysterically to be let in. In a like vein, David Letterman and his bizarre female stalker have nothing on Connecticut neighbor Ivan Lendl, the Czech/American tennis star who used to be plagued by a strange woman named “Gemma” seeking him out at home and away and even at the office of his agent at the time, Jerry Solomon, now Kerrigan’s business manager.

“Athletes now have to start worrying about their own security,” says Bob Kain, vice president of International Management Group, which handles Seles, Joe Montana and Arnold Palmer, to drop just a few names. So Muhammad Ali occasionally took on as a bodyguard the ever dangerous, bejeweled Mr. T. So Magic Johnson–on the advice of friends Arsenio Hall and Eddie Murphy–hired himself a bodyguard who promptly punched out Buffalo Bills linebacker Darryl Talley at an L.A. nightclub prior to last year’s Super Bowl. So Atlanta Braves Ron Gant and Mark Lemke both own permits to carry concealed weapons. So Atlanta Falcon Andre Risen fired a warning shot outside a nightclub with his unconcealed weapon. And so Falcon teammate Jamie Dukes says in opposition: “I try not to put myself in a situation where I know there could be a gangland shooting.”

Always a good idea. As is signing up, say, Kevin Costner to cover your athletic butt. It wasn’t Whitney Houston who started the modern bodyguard craze among celebrities, though. Tennis player Jimmy Connors’s burly New York friend Doug Henderson would also double as a bodyguard, surrounding Connors between matches at the U.S. Open. “Neon” Deion Sanders, he of football and baseball fame, used to gain personal protection, amateur division, from two live-in Florida homeboys he introduced as “Heckle and Jeckle.” Then there’s boxer Mike Tyson and baseball’s Bobby Bonilla, Eric Davis and David Cone, all of whom have employed Nelson Mercado of Santa Ana, Calif., a real, live, professional bodyguard who once studied at the knee of G. Gordon Liddy. “He would take a bullet for you,” says Cone.

“I look for eye movements, security, behavior,” says Mercado. “Dead clients don’t pay.” “Bodyguards?” Charles Barkley, the basketball star who seems to involve himself in some sort of scuffle every season, reportedly once joked. “That wouldn’t be no fun–you wouldn’t get to beat them up yourself.”

Though it’s true that variables such as individual versus team sports, players with light clothes against those with protective equipment and women versus men undoubtedly determined the likelihood of attack in the Seles and Kerrigan incidents–who you gonna try, Lawrence Taylor? Shaquille O’Neal?–there’s enough crazy stuff going on out there to make every athlete concerned. If Seles’s tragedy was once considered an aberration, Kerrigan’s seems a clarion call to increased vigilance. “Now there’s a second one, there may be copycats. More people will react now,” says Kain. “I’ll probably get calls from clients saying, let’s look at this a little more seriously.” They should. “Security is not an expense,” says Mercado. “It’s an investment.”

The new athletic drill: Tape your ankles. Stretch your muscles. And watch your back.