Most intriguingly, the Phils will find in Bonds a man impervious to his designated role of top villain in baseball's sordid steroid era.
Mark McGwire? Rafael Palmeiro? Jose Canseco? Bush-leaguers, all, in this unpopularity contest.
Because he outlasted his competition, because he has dared last long enough to flirt with a most storied record, Bonds is truly reviled.
Many a critic had hoped Bonds would not only fade away well short of Aaron. They fervently wished he would also drown in a torrent of indictments, subpoenas and suspensions.
The thing is, it hasn't happened.
Batboys turned steroid pushers turned government witnesses have fallen. Major- and minor-league users such as former big-league pitcher Jason Grimsley have, too. Just not Bonds.
Those caught are naming names and leaking to the media like sieves. But Bonds has yet to be slimed in a way that takes him off the field and into a court of law.
Joe Morgan, the Hall of Famer and color commentator who will call the Phillies-Giants game Sunday (8 p.m., ESPN, ESPN Deportes), suspects he knows why.
"If Barry's name had been on that list that was blacked out, we would have known about it," Morgan said, referring to a federal government affidavit concerning a former Mets clubhouse employee who has admitted providing steroids and other drugs to major-leaguers. "Same with Jason Grimsley.
"A lot of people's agendas are about getting Barry. Remember, his name came out for failing that amphetamine test. You can't tell me Barry was the only one that failed, but his was the only name that came out."
No doubt Bonds will always remain guilty in the minds of most fans. There is no argument, though, that he also remains amazingly elusive to those empowered to throw the book at him.
So Bonds plays on, his confidence, like his health, again intact.
"The media, the government, the fans have tried to get Barry for four years," Morgan said. "They can't stop him. Say this about Barry: He is able to focus on his agenda, period. He doesn't care what I say, what you say, or what anybody else says."
Like him or hate him, you have to marvel at his sheer stubbornness, both physical and mental.
The seven-time league MVP, who is 42, looks again like the slugger who hit 258 home runs from 2000 to '04, not the broken-down guy with bum knees who played just 14 games in 2005.
It is this rejuvenated Bonds who is raising a host of prickly issues to even greater heights.
Opposing managers, who again fear him as much as many fans loathe him, are again shying away from challenging Bonds. Witness the 23 walks drawn by Bonds in his first 23 games.
"On the road, fans boo Barry when he comes to the plate, then they boo even louder if he's walked," said Morgan's booth partner, Jon Miller, who is also a Giants broadcaster. "One way or the other, they came to see Barry and they feel they're being ripped off."
Ambivalence grips others, as well. Baseball's bigwigs (i.e., commissioner Bud Selig) must decide, and quickly, whether to ignore, endorse, or even witness the inevitable.
No sympathy there. After all, this is a game that ignored cheating right up until stats bloated by whatever could no longer pass the smell test.
Aaron is a different story.
Nobody much cared what this quiet, humble man thought in 1974 when then-commissioner Bowie Kuhn unconscionably skipped Aaron's breaking of Babe Ruth's mythic record of 714 home runs.
If Selig decides to stiff Bonds similarly, the opinion no one wanted from Aaron 33 years ago will suddenly matter. Already, Aaron's decision not to witness the fall of his record has become an issue.
"Hank is in a no-win situation," Morgan said. "He has told me, 'I don't think you can condemn a person without proof.' Yet he also said he doesn't want to be a part of what happens, and you can't blame him, not when the first question inevitably will be, 'Do you think Barry cheated?'
"If he answers no, he'll be called a liar. If he says yes, it's sour grapes. Already, some guy in Detroit wrote 'Hank Aaron is a coward.' A coward!"
The question we must ask ourselves, Morgan said, is: What is it exactly that we want from Aaron?
We already know what we want from Bonds. We won't get it, though, because Barry is only about what he wants, the rest of the world be damned.
Contact staff writer Claire Smith
at 215-854-4577 or email@example.com.
Read her blog at http://diamondinq.blogspot.com.