Indy Is a Family Affair for Unsers, Andrettis; Lowdown on Yankees' Slugger

TWO of the greatest families in American auto racing - the Unsers and the Andrettis - were case studies Sunday in the thrills and frustrations that accompany their sport.

The Unsers wound up on the thrill side of the ledger, with Al Unser Jr. driving to his second Indianapolis 500 victory as his misty-eyed father, a four-time Indy winner who retired just two weeks ago, looked on from the pits.

The win was quite a birthday present yesterday for the senior Unser, who shared a victory lap in the pace-car Sunday with his son.

For the Andrettis, Sunday brought exasperation with a modicum of achievement.

Mario Andretti, who is in his last year on the IndyCar circuit, wound up 32nd in a 33-car field while making his last competitive appearance at the Indianapolis Speedway.

The 1969 winner was forced out of the race on lap 23 by a mechanical problem, an all-too-familiar refrain for the veteran driver. This time it was a faulty fuel pressure relief valve that costs less than $50.

Papa Andretti took consolation in the efforts of his son Michael and nephew John.

Michael was sixth at Indianapolis and John 10th.

John also accomplished his goal of competing in both the Indy 500 and the Coca-Cola 600 at the Charlotte (N.C.) Motor Speedway on the same day.

Because he missed the drivers' meeting two hours before the start of the 600-miler, though, he had to start at the back of the field of 43 stock cars.

He hit the retaining wall on lap 89 and retired from the race with a broken crankshaft. Altogether, he completed 820 miles of a possible 1,100 in his two-race marathon. Scouting scoop on hit sensation

ALTHOUGH New York Yankees outfielder Paul O'Neill is not the least likely guy to be batting .456 at this stage of the major-league baseball season, he is hardly the most obvious choice either - even on his own team. After all, five-time American League batting champion Wade Boggs (1983; '85-'88) is among his teammates, as is Don Mattingly, who copped the honor in 1984.

Then, too, O'Neill's career batting average entering this season was a modest .268. He did hit .310 last year, though, his first since coming over to the Yankees from the National League's Cincinnati Reds. The book on him, as found in ``The Scouting Report: 1994,'' a project of STATS, Inc., a consortium of baseball statisticians and reporters, is that O'Neill is a terrific fastball hitter who benefits from being platooned (held out against tough left-handed pitchers).

Over the last five years the left-hand-hitting O'Neill has batted only .219 against southpaws. Yankee manager Buck Showalter continues to sit him down against certain lefties, but if his average continues to soar, the paying public won't be too thrilled to see him riding the pine. Illinois mascot shunned

THE University of Illinois has been put on notice that its mascot, Chief Illiniwek, is not universally welcome anymore. The University of Iowa recently joined two other Big Ten Conference members in banning the mascot from athletic events on their campuses.

In a related development, Marquette University became one of the latest schools to achieve political correctness by renaming its sports teams, switching from Warriors to Golden Eagles. Though the school long ago dropped a Willie Wampum caricature, even the use of a more respectful Indian warrior was sensitive in Wisconsin, which has a sizable Native American population. Touching other bases

* A possible coach-pupil match exists in men's tennis this year. Brad Gilbert, the coach in this case, doesn't think his pupil Andre Agassi has much to worry about. ``He's got bigger fish to fry,'' says Gilbert of the tour's 20th-ranked player. Gilbert is No. 32.

* Through his niece's experiences as a determined teen-age tennis prodigy, Boston Globe sports columnist Dan Shaughnessy has seen of how young women - some perhaps like troubled star Jennifer Capriati - are drawn ever tighter into the sport's clutches. Costly lessons can be one factor in upping the ante. In the case of Shaughnessy's niece, her parents are considering a pay-back deal with her coach: His lessons in exchange for a guaranteed percentage of her future tennis earnings. It's easy to see how this would create performance pressures.