Armstrong retired after winning a seven consecutive Tour de France in 2005 but decided to return to the sport in 2009. His first race on his comeback came at the Tour Down Under with Astana. He would go on to finish third at the 2009 Tour de France. Armstrong then rode the next two editions of the Tour Down Under for his RadioShack team.
In January 2013, on the eve of Tour Down Under, Armstrong admitted to doping throughout his career in a television interview with Oprah Winfrey. He received a life ban from the sport and lost his Tour de France titles.
"If you had asked me three years ago, I would have said 'absolutely' (I regret the comeback), but where I sit today, five years post, I wouldn't change a thing," Armstrong told the Advertiser.
Armstrong finished 29th in 2009, 24th on his second appearance, and 67th in 2011. Despite not challenging for the podium, crowd numbers, coverage of the race and interest spiked with Armstrong's appearance at the race. Armstrong also organised several "Twitter rides" that attracted several thousands of cyclists.
Asked to rate his contribution to the race, Armstrong said it was "100 per cent positive".
For race director Mike Turtur, the Tour Down Under is "still benefitting from that legacy" of the Armstrong years. "The smallest increase that we saw was 100 per cent it."
South Australia sports minister Leon Bignell added to Turtur's comments, adding that Armstrong "put our race on the map" according to the Advertiser.
Armstrong was reportedly paid one million dollars for each Tour Down Under appearance, although the State government has not revealed its race fee for the American.
"Lance Armstrong's appearance at the Santos Tour Down Under came at a time when he was considered the greatest cyclist in the world. He brought the eyes of the world with him to South Australia when he rode in the TDU, taking the race to a whole new level," added Bignell.
"The state government has continued to leverage this exposure, ensuring crowd numbers continued to climb even after Lance's final TDU appearance."
In 2008 the Tour Down Under attracted 548,000 spectators with the crowd numbers for the 2017 edition of the race estimated at 840,000.
The 2018 edition of the Tour Down Under takes place January 14-22.