New York ? Baseball relies on numbers the way the Earth relies on gravity.

So the conundrum facing the game at the start of its new season is awkward at best, devastating at worst: Arguably its most hallowed statistical record is under assault by a man who is – unarguably, at the moment – its most vilified player.

The man is Barry Bonds, left fielder for the San Francisco Giants, owner of 708 career home runs and public focal point of a furor over steroids and other performance-enhancing drugs in baseball.

The scandal, now under investigation by former Senate Majority Leader George Mitchell, comes at what should be a time of celebration: Today is opening day for most teams, and Bonds is closing in on Hank Aaron’s record of 755 lifetime homers.

“The goal here is to determine facts,” baseball commissioner Bud Selig said in announcing the investigation.

But for a game whose beauty rests in its certainty – clean lines, clear rules, ball or strike, out or safe – the steroids controversy has raised an awful lot of questions with murky answers, or no answers at all.

Example: How can Bonds, who was booed roundly in spring training appearances, alone be the object of such intense rage by fans when so many other players blew up like Macy’s parade floats beginning in the 1990s, era of the baseball power surge?

And how can baseball gain credibility by announcing an investigation only now, when it had anonymous test results showing players were doping in 2003? And when it only banned performance-enhancers a year before that?

“Why didn’t they do amphetamines in the 1970s?” wonders Daniel Okrent, a former public editor of The New York Times who has written extensively about the game. “I think that baseball generally does things like this when they have no choice.”

In the case of steroids, he was referring to pressure from Congress, which hauled several sluggers before a committee last year. At that hearing, the mammoth Mark McGwire would offer only a meek, “I’m not going to talk about the past.”

The Mitchell probe was triggered by the publication of “Game of Shadows,” by two San Francisco Chronicle reporters, which claims Bonds began taking steroids after he watched McGwire, then beloved, break the single-season home run mark in 1998.

The book portrays Bonds, who offensive production subsequently ballooned, as taking an array of performance enhancers that would make a pharmacist dizzy – hormones, steroids, fertility drugs for women.

Bonds, who has denied using steroids, opens the season 47 home runs shy of the record. He has hit 45 or more in five separate seasons since “Game of Shadows” alleges he began his drug regimen.

The question raises the issue of whether, presuming Bonds breaks the record and is found to have used steroids, his numbers should be scrubbed from the books, or marked with the infamous asterisk.

Okrent argues the numbers should stand, just as they do despite changes in the length of seasons and the conditions under which the game is played.

“A record is a record,” he said. “You can carry whatever asterisk in your head – the 162-game season, players who didn’t have to ride trains all night, whatever it might be.”

In other words, the entire beefed-up era may carry a permanent taint no matter what the records reflect.

As columnist and longtime fan George F. Will observed in a column in March: “The people who care about the record book – serious fans – will know how to read it. That may be Bonds’ biggest worry.”

Complicating the issue, some players have said that public criticism of Bonds, who is black and has long had a chilly-at-best relationship with sports writers, is motivated by race.

“It’s a very difficult question,” said Selig’s predecessor, Fay Vincent. “I don’t think so, but I can see where race is a huge problem in American history and we’re going to be dealing with it indefinitely. How can you prove a negative?”

It is impossible to say what role race will play in the chorus of boos Bonds is likely to hear this season, particularly on the road. The Giants begin their season with three games in San Diego, starting Monday.

But the steroid furor makes for a far different atmosphere than Aaron faced in 1973 and 1974, when he faced racial slurs and death threats as he chased and eventually toppled Babe Ruth’s home run record of 714.

If Bonds plays up to his potential, he could pass Ruth in the new season’s opening weeks. And until the facts are clear, Aaron, for one, was preaching caution and fairness in a recent interview with The Atlanta Journal-Constitution.

“I don’t know the answer, and I don’t think anybody does,” the reigning home-run king said. “We all sit here and try to pretend that we do, but we really don’t. Until you’re proven guilty, you’re innocent.”