On the night Barry Bonds crushed his 73rd home run of 2001, setting the single-season record that still stands, he was 36 years old — an age when most hitters are already declining. His neck had expanded, his hat size had grown, and his home-run frequency had virtually doubled from the previous decade. The question of when, exactly, that transformation began — and what drove it — sits at the center of one of the most documented PED scandals in sports history. The BALCO investigation, grand jury transcripts, seized doping calendars, and the testimony of those closest to Bonds paint a detailed, if contested, picture. This is the complete timeline of the steroid era’s most polarizing figure.

The Before: Barry Bonds Without PEDs (1986–1997)

A Hall-of-Fame Career Already in Progress

To understand the timeline of Barry Bonds’ alleged PED use, it is critical to acknowledge his baseline. Before the 1998 season, Bonds was already widely considered the greatest active player in baseball and a guaranteed first-ballot Hall of Famer. Between 1986 and 1997, he secured three National League MVP awards, eight All-Star selections, and eight Gold Gloves for his elite outfield defense. By 1996, he was a member of the ultra-exclusive 500 Home Run and 500 Stolen Base club.

The Slender ‘Five-Tool’ Player Pittsburgh Knew

Physically, the pre-1998 Barry Bonds was a slender, athletic “five-tool” player weighing around 185 to 190 pounds. His home run production was elite but steady, averaging one home run for approximately every 16.2 at-bats. Over those first twelve seasons, he amassed 374 home runs, a .288 batting average, and 1,094 RBIs in 1,742 games. His physiological profile and statistical output during this era serve as the benchmark against which his later, highly anomalous years are measured.

The Turning Point: 1998 and the McGwire–Sosa Effect

How the Great Home Run Race Changed Bonds

Investigative consensus, primarily detailed in the landmark book Game of Shadows by San Francisco Chronicle reporters Mark Fainaru-Wada and Lance Williams, pinpoints 1998 as the year Bonds initiated his PED regimen. That summer, the nation was captivated by the great home run race between Mark McGwire (who finished with 70 home runs) and Sammy Sosa (66). According to witness testimony and extensive investigative reporting, Bonds—who believed he was a fundamentally superior player to both—was deeply resentful of the attention they received and made the calculated decision to “get on the program.”

First Contact With Greg Anderson and BALCO

In pursuit of this new physical paradigm, Bonds turned to his childhood friend and personal trainer, Greg Anderson. Anderson would soon become the critical link to the Bay Area Laboratory Co-Operative (BALCO), founded by Victor Conte. As Bonds entered the 1999 season—his first full year training under Anderson’s new protocols—his physical transformation accelerated rapidly, kicking off what investigators allege was a minimum five-year regimen of sophisticated doping.

The Substances: What Was ‘The Clear’ and ‘The Cream’?

THG (Tetrahydrogestrinone): The Designer Steroid

The cornerstone of the BALCO doping regimen was a designer anabolic steroid known colloquially as “The Clear.” Chemically identified as tetrahydrogestrinone (THG), it was a synthetic derivative of gestrinone created specifically to evade the drug tests of the late 1990s and early 2000s. Administered sublingually (under the tongue), THG remained completely undetectable until June 2003, when a whistleblower provided a syringe of the substance to the U.S. Anti-Doping Agency, leading to its identification by Dr. Don Catlin at the UCLA Olympic Analytical Laboratory.

‘The Cream’: Testosterone + Epitestosterone Topical

The second pillar of the protocol was “The Cream,” a topical balm containing a precise mixture of testosterone and epitestosterone. In doping control, a high ratio of testosterone to epitestosterone (T:E ratio) triggers a positive test. “The Cream” was chemically engineered to elevate testosterone levels while simultaneously delivering enough epitestosterone to keep the ratio within passing limits, effectively masking the synthetic hormone surge. During his grand jury testimony, Bonds admitted to using both substances but claimed Anderson told him “The Clear” was nutritional flaxseed oil and “The Cream” was a benign arthritis rub.

Peak Performance and the Statistical Anomaly (1999–2004)

73 Home Runs in 2001: A Record That Defied Aging Curves

From 1999 to 2004, Bonds’ statistical output defied all established biological aging curves for professional athletes. Over this span, he hit 388 home runs in 1,244 games. His home run frequency nearly doubled to an astonishing 1 HR per 8.5 at-bats. In 2001, at the age of 36, he shattered the single-season record by hitting 73 home runs. A physiological analysis published by the NIH demonstrates that even a 10% increase in fast-twitch muscle mass exponentially increases bat speed and the resulting physical force applied to a baseball, making such statistical anomalies possible.

Four Consecutive MVP Awards and the Physics of Power

During this same window, Bonds won an unprecedented four consecutive National League MVP awards (2001–2004). His physical evolution was undeniable: his head, neck, and overall body mass expanded dramatically, necessitating larger hat, shoe, and jersey sizes. While other players linked to BALCO—such as Jason Giambi and Gary Sheffield—also experienced late-career power surges, Bonds’ statistical divergence was so profound that it rewrote the physics of the sport.

The BALCO Investigation: Federal Agents Close In (2002–2004)

The September 2003 Raid on BALCO

The facade began to crumble in 2002 when federal agencies, including the IRS and DEA, launched a comprehensive investigation into BALCO’s finances and medical practices. In September 2003, federal agents raided BALCO headquarters in Burlingame, California, along with Greg Anderson’s home. Agents seized steroids, syringes, cash, client files, and highly detailed doping calendars mapping out specific cycles for elite athletes.

The Grand Jury: Bonds Testifies in December 2003

In December 2003, Bonds was subpoenaed to testify before a federal grand jury under a grant of immunity—meaning he could not be prosecuted for drug use, provided he told the truth. Under oath, Bonds testified that he used the substances provided by Anderson but staunchly denied knowing they were steroids. In 2004, the San Francisco Chronicle leaked transcripts of this testimony, triggering a massive public scandal. Subsequently, Victor Conte and Greg Anderson were hit with a 42-count federal indictment.

The Legal Saga: Indictment, Trial, and Overturned Conviction (2007–2015)

2007 Indictment: Perjury and Obstruction Charges

While figures like Victor Conte and Greg Anderson pleaded guilty to distribution charges by 2005, the federal government spent years building a perjury case against Bonds. Anderson was repeatedly jailed for contempt of court between 2006 and 2007 because he absolutely refused to testify against his friend. In August 2007, amidst a dark cloud of public suspicion, Bonds broke Hank Aaron’s all-time career home run record. Just three months later, a federal grand jury indicted Bonds on four counts of perjury and one count of obstruction of justice for his 2003 testimony.

2011 Trial Verdict and the 2015 Reversal

The trial finally concluded in April 2011. The jury deadlocked on the perjury charges (which were subsequently dropped) but convicted Bonds on the single felony count of obstruction of justice, stemming from a rambling, evasive answer he gave to the grand jury regarding whether Anderson ever injected him. He was sentenced to two years of probation and 30 days of home confinement. However, the legal saga ended in 2015 when a panel of the Ninth Circuit Court of Appeals voted 10-1 to overturn the obstruction conviction, ruling that his evasive answer was not materially obstructive. Legally, Barry Bonds was fully exonerated and was never criminally convicted of steroid use.

Legacy: Hall of Fame Snub and the Steroid Era’s Lasting Shadow

Ten Years on the BBWAA Ballot — Never Inducted

Despite his legal exoneration and his status as the all-time home run king (762 HRs), Barry Bonds remains excluded from the National Baseball Hall of Fame. Over his 10 years of eligibility on the Baseball Writers’ Association of America (BBWAA) ballot, he peaked at 66% of the vote, falling short of the required 75%. In 2023, the Contemporary Baseball Era Committee also rejected his induction. The debate continues: Does a player who amassed Hall of Fame statistics prior to 1998 deserve induction, or does the stain of the steroid era invalidate the entirety of the record?

What Bonds’ Case Revealed About Drug-Testing Failures

The BALCO scandal, centered around Bonds, permanently altered the landscape of professional sports. Following the 2005 Congressional hearings on baseball steroids and the explosive 2007 Mitchell Report, Major League Baseball was forced to implement the Joint Drug Agreement, enacting strict penalties and comprehensive testing. Globally, the discovery of THG pushed the World Anti-Doping Agency (WADA) and USADA to adopt advanced mass spectrometry testing methods and retrospective sample testing, ensuring that designer steroids could no longer hide in the shadows.