Editor's note: Mark Purdy is a sports columnist for the San Jose Mercury News and is covering the Barry Bonds trial.

San Francisco, California -- Each year at this time, baseball loves to put on its best face. Unfortunately, this year the game's springtime face has an ugly pimple from its past that simply won't fade away.

Opening day is at hand. But when Major League teams begin play on Thursday, the game's all-time leading home run hitter will not be throwing out a ceremonial first pitch. Barry Bonds will be sitting in a courtroom as a defendant, facing possible jail time for allegedly lying to a grand jury about his use of steroids in 2003.

Nostalgia is a big part of baseball. But this sort of nostalgia is not preferred. The Bonds trial is leftover debris from a time that Major League commissioner Bud Selig wishes desperately to put behind him, a time when performance-enhancing drugs were allowed to practically take over the game because of lax testing standards.

Indeed, if the timing is just right -- or just wrong -- it is possible that the Bonds verdict will be announced on April 8 during the Giants' home opener at AT&T Park, barely two miles down the street from the local federal courthouse.

The trial began March 21. And instead of "play ball," the most frequent phrase being tossed around the courtroom is the cringe-inducing "testicular atrophy." Bonds' former mistress, one-time Playboy model Kimberly Bell, testified yesterday that Bonds' male organs became smaller as a side effect of his steroid use.

Meanwhile, the jury has already heard an audio tape in which Bonds' former trainer was caught speaking about "gnarly" buttock cysts that are a consequence of steroid injections. And a former business partner of Bonds has testified that he kept hundreds of thousands of dollars in cash handy for payments to the ballplayer's two mistresses during his two marriages.

Full coverage of Bonds trial

At a time when Giants fans are still celebrating the World Series title their team won last autumn, they are not exactly thrilled to hear such smarmy reports from the witness stand about a player to whom they once gave loud standing ovations at the team's signature waterfront ballpark.

How are those fans coping? The other day, shopper Bob Laupp of San Jose emerged from the Giants Dugout Store at Westfield Valley Fair Mall, one of the Bay Area's largest retail complexes. Laupp said he was a longtime fan of the team. His father, he said, took him to see Willie Mays play at Candlestick Park in the 1960s. Laupp has been hooked on the Giants since.

"The trial hasn't had any effect on what I feel about this current team," Laupp said. "It is what it is. Who knows how many other players have done what Bonds did? Sometimes I think: 'Who hasn't done it?' "

Selig must wince at that remark. In 2005, he negotiated tougher enforcement on steroids with the players' union. But the perception remains that baseball has been softer on its drug criminals than other sports. In 2007 when Bonds surpassed one of the game's most sacred milestones -- Hank Aaron's lifetime home run total of 755 -- the skeptics bore down with a vengeance. In response, the fractious Bonds defiantly snapped: "This record is not tainted at all. Period."

Technically, the current case is not about that record. It is not about whether Bonds used steroids a dozen years ago when he bulked up his frame and began smacking homers at a dizzying pace. Rather, the case is about whether Bonds lied when he was called to testify before the 2003 grand jury that was investigating a steroids-conspiracy case against a Northern California medical supplement company called BALCO (Bay Area Laboratory Cooperative).

Bonds and several other athletes were told before their testimony that nothing they said could be used to charge them with any crimes as long as they told the truth. Bonds was then asked if he had ever used performance-enhancing drugs from BALCO that had been supplied to his trainer, Greg Anderson. Bonds replied: "Not that I know of."

It was the baseball steroid scandal version of: "I never had sex with that woman." Nuance was the issue.

Anderson pleaded guilty in 2005 to steroid distribution and served three months in jail. However, Bonds claimed his testimony was correct because Anderson had told him that the illicit substances he provided -- an ointment called "the cream" and a liquid called "the clear" that allowed users to pass urine tests -- were arthritis balm and flaxseed oil.

Prosecutors didn't believe him. In 2007, they indicted Bonds based on his original statement and his sworn testimony that he had never received injections of any substance from anyone other than his doctors. Anderson would be the most obvious person to affirm or refute the government charges. But after serving his 2005 sentence, he has consistently refused to cooperate with the government or to testify. U.S. District Judge Susan Illston cited him for contempt last week and ordered him back to jail -- where he sits today as the Bonds trial unfurls.

The drama has aroused the Bay Area's curiosity in a big way, even among people who aren't fans. During jury selection, attorneys rejected one potential panelist who admitted that she couldn't be objective about the case, saying: "I was at the grocery store the other day, and two people in front of me, that's all they could talk about."

Another prospective juror wrote bluntly on a questionnaire that she could be objective for one reason: "We all know Mr. Bonds is a jerk, but he is not being prosecuted for that."

She wasn't selected, either.

Legal experts say that even if Bonds is convicted, he is unlikely to do serious jail time. Other athletes found guilty of lying under oath in the BALCO case have received very short terms or home confinement. But win or lose, Bonds' never-loveable image will take a hit by the public airing of his dirty laundry. And none of it will be good for baseball.

Example: The trial's most dramatic moment so far occurred when prosecutors played the audio tape of Anderson speaking to former Bonds business partner Steve Hoskins in the Giants clubhouse during the 2003 season. On the tape, in the midst of a conversation about the proper way to inject steroid needles, Anderson momentarily pauses to say as an aside, "Hi, Benito," (Santiago, the Giants catcher at the time). Anderson then casually continues the conversation.

Apparently, in those days, performance enhancing drugs were so prevalent that Anderson felt comfortable discussing them within earshot of the entire Giant roster. A further reminder of that era will surface in a few months. Former pitcher Roger Clemens, the game's only seven-time Cy Young award winner, will face his own perjury charges for making alleged false statements about his steroid use to a 2008 congressional panel.

Clemens' trial should begin in July, right before the All-Star Game. For Selig and his sport, this is going to be a long, pimply season.