Cycling: George Hincapie's confession will hurt Lance Armstrong the most

Were it not for the huge uproar created by the release of the US Anti-Doping Agency's files yesterday, the decision by George Hincapie – Lance Armstrong's long-term team-mate at US Postal, and key lieutenant – to confess to the use of banned drugs prior to 2006 would in itself mark another major milestone in the demolition of the multiple Tour-winner's credibility.

One of Armstrong's most frequently used defences has been that some of the riders who have denounced him and the Postal team are– he claims – not believable because of their former vigorous denials of doping.

On top of that, a large proportion of the rest of those who have pointed the finger ended up either falling foul of Armstrong at Postal or simply receiving better offers from other teams and quitting the Texan's squad. Hincapie, though, has no axe to grind, no grudges – and never left Postal.

In fact, Hincapie was Armstrong's most trusted lieutenant throughout his Tour victories from 1999 to 2005, to the point where he and Armstrong were the only riders to form part of the line-up on all of Armstrong's Tour-winning teams. If Armstrong was the leader, "Big George", as he is affectionately known, was the ultra-reliable team captain, often described as Armstrong's best friend. Long after Armstrong had quit, Hincapie continued to motor on: earlier this year, he became the first rider ever to ride a record-breaking 17 Tours de France, completing 16.

Nearly two metres tall and heftily built, Big George's victory at the ski station in the Pla d'Adet in the 2005 Tour – after dragging his huge bulk across one Pyrenean climb after another – saw him hailed as a breakthrough: suddenly a former "non-climber" briefly became the team's prospect for winning the race outright after Armstrong's imminent retirement at the end of the season. Given Hincapie has now said he raced clean after 2006 up until his career ended earlier this season – which dovetails with Armstrong's retirement from the sport at the end of 2005 – one possible explanation for how Hincapie suddenly became so talented whenever the roads steepened in his latter days alongside the Texan becomes jarringly clear.

Hincapie, just as Armstrong has often repeated about himself as yet another line of defence, has never tested positive – further evidence, if it was needed, that doping tests at the time only acted as the most limited of deterrents given how easy they were to avoid.

Yet there, on his website yesterday, was a typically understated declaration from the 39-year-old New Yorker, one of the quietest and – it has to be said – most popular riders in the peloton, confessing that he – like former Postal riders Tyler Hamilton, Floyd Landis, Jonathan Vaughters and Frankie Andreu – had doped during the first part of his career.

"Because of my love for the sport… it is extremely difficult to acknowledge that during a part of my career I used banned substances," Hincapie said in a statement. Tellingly, just like Landis and Hamilton, the reason he gave for doing so was that "early in my professional career, it became clear to me that given the widespread use of performance-enhancing drugs by cyclists at the top of the profession, it was not possible to compete at the highest level without them. I deeply regret that choice."

Hincapie had already retired at the end of this season, but his confession is a bombshell that isolates Armstrong in his insistence of innocence to a point which is almost pitiful – and that is even without Usada's publication of its investigation.

Hincapie's confession is the latest of a series of body blows to Armstrong's credibility that stretches back to an allegedly covered-up positive test for corticoids in the 1999 Tour de France, through the publication of David Walsh's LA Confidentiel book in 2004 – which partly lifted the lid on the suspicions surrounding Armstrong – and the allegations by L'Equipe in 2005 of positive tests for EPO, the drug of choice, for Armstrong in the 1999 Tour.

However, the wealth of detail on organised doping in Postal provided by former team-mate Floyd Landis in an emailed confession sent to the USA cycling authorities and Usada in 2010 was arguably the key turning point in uncovering the vast network of doping practices at the team. Shortly afterwards, the US federal authorities began a full-blown investigation into Postal, headed by their top investigator, Jeff Novitzky, who had worked on the Balco doping case. Witnesses, such as Hamilton, Landis and Hincapie, were all subpoenaed to testify and in the words of Hamilton in his book The Secret Race, "they had to tell the truth or risk going to jail for perjury".

"In short, it was Lance's worst nightmare – a powerful, sharp-edged legal enquiry into how he had won the Tour de France," wrote Hamilton.

Even though that case was dropped – for reasons that have never been fully made clear – it is widely believed, although not officially confirmed, that federal authorities passed on evidence and statements to Usada, some of which may well have found their way into what was due to be published yesterday. But Hincapie's confession may well be more painful for Armstrong to handle on a personal level.

"Three years ago, I was approached by US federal investigators, and more recently by Usada, and asked to tell of my personal experience in these matters," Hincapie said yesterday.

"I would have been much more comfortable talking only about myself, but understood that I was obligated to tell the truth about everything I knew. So that is what I did."

Whether this latest series of revelations, coupled with Hincapie's confession, will prove one turn of the screw too many for Armstrong, however, remains to be seen.

I was dope cheat, admits Sky rider

Team Sky was dragged into the scandal yesterday when Michael Barry confessed to doping while he was at US Postal from 2002 to 2006. The Canadian joined Team Sky in 2010 and retired this year. Yesterday, he apologised "to those I deceived", and added, "in the summer of 2006, I never doped again... I chose to race for teams that took a strong stance against doping."

Who's who: Key figures in US Postal scandal

Floyd Landis

Armstrong's US Postal team-mate admitted to doping in 2010, which led to him being stripped of his 2006 Tour de France victory. In 2010, he accused former team-mates, including Armstrong and George Hincapie, of blood doping from 2002-2004.

Tyler Hamilton

A member of Armstrong's Postal team for his Tour wins of 1999, 2000 and 2001. Hamilton went on US television last year to implicate Armstrong in the team's alleged doping. He has since written a book, 'The Secret Race', revealing the team's doping methods.

George Hincapie

Armstrong's right-hand man during all of his Tour de France successes. Confessed to doping yesterday.

Michael Barry

Recently retired, the Canadian rode as a domestique for Team Sky from 2010. Admitted to doping yesterday when at Postal and apologised for his role in it from 2002 to 2006.

Johan Bruyneel

The Postal team director from 1999 to 2007 is fighting the charges against him from Usada.

Timeline: How Armstrong doping saga unfolded

Tour triumph: 24 July 2005

Lance Armstrong retires after record seventh Tour de France triumph, and hits back at critics in his speech, saying: "'I'm sorry you don't believe in miracles." He returns to the sport in 2009, but retires again in 2011.

Claims emerge: April '10

Armstrong's former Postal Service team-mate Floyd Landis accuses him of an extensive doping cover-up, and claims the team were involved in blood doping. Hamilton goes public: May '11

Another former team-mate, Tyler Hamilton, tells US news programme 60 Minutes that Armstrong personally oversaw team's doping programs. "I saw him inject EPO," said Hamilton.

Usada starts proceedings: June '12

The United States Anti-Doping Agency notifies Armstrong that formal procedures against him have commenced over allegations he used performance-enhancing drugs. In response, Armstrong releases statement describing the allegations as "baseless".

Later in the month, Usada review board unanimously recommends bringing charges, meaning the case will go to an arbitration if the charges are challenged.

Lawsuit dismissed: July '12

Armstrong files a federal lawsuit seeking to stop Usada from proceeding with their case. But later that day, a federal judge dismisses his lawsuit.

Three banned: July '12

Three former associates of Armstrong are given lifetime bans for involvement in the alleged doping – doctors Luis Garcia del Moral and Michele Ferrari and trainer Jose "Pepe" Marti.

Stripped of titles: August '12

Armstrong announces he will no longer fight the doping charges made against him by Usada. The anti-doping body then says it will strip him of all results dating back to August 1998.

Usada verdict: Oct '12

Usada releases report, more than 1,000 pages long, on its doping case against Armstrong and the Postal team, concluding there was "conclusive and undeniable proof" of team-run doping.