In an interview with a small group of journalists in Amsterdam, Coe launched a fresh plea for athletes to turn informants should they encounter doping, saying it was a "historic moment" for athletics.
Stepanova herself served a two-year doping ban before she and her husband Vitaly made startling revelations about state-sponsored doping in Russian athletics.
Associated, widespread corruption with the International Association of Athletics Federations (IAAF) plunged the body into its worst-ever crisis, just as Coe was installed as president in place of now-disgraced Lamine Diack.
But Stepanova, now exiled in the United States, was handed the chance to compete as a "neutral" as recompense for her speaking out on the systematic doping at the heart of Russian athletics.
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"She fulfilled the eligibility criteria set down by the IAAF taskforce and anti-doping review board and the invitation was at the behest of European Athletics," Coe said of Stepanova, who tore a ligament in her heel during her 800m heat on Wednesday and was later disqualified.
"You have to be consistent. If you are asking athletes to step up to the plate and not just be commentators sitting in the background ... Then I think you have to say that those that are prepared to do that should be recognised for that.
"They do need to be in a position where they're really
prepared to stick their heads above the parapet. They know more about it than any of us. They're there, at the side of the track, they're in the training groups, they know the coaches not doing it with integrity. They can help us and that's really important."
"And I make this offer to all athletes. If you think you can help us get through this pathology quicker, if you can help us understand the nature of the challenge that we're dealing with... It's a golden opportunity that is not necessarily going to present itself again for our sport to grab this moment, this is a historic moment."
Coe confirmed that 136 Russian athletes had applied to the IAAF for the right to compete at the Rio Games. Each would be examined on a case-by-case basis, he said, refusing to discuss individuals.
The former middle-distance runner, who won two Olympic 1500m gold medals for Britain in the 1980 and 1984 Games, said he had felt bolstered by the support he had received from other sports.
"The federation presidents, the senior members of the executive board, the larger NOCs (National Olympic Committees), we all coalesced around the concept of creating a level playing field for competitors.
"This is a really important moment, not just for my sport but sport more broadly.