IOC President Thomas Bach spoke to Peng Shuai for 30 minutes on SundayCriticism of the International Olympic Committee's handling of the Peng Shuai situation is "complete nonsense", says senior IOC official Dick Pound.
But the call was criticised by tennis leaders and human rights groups for not addressing concerns over her wellbeing.
Pound said the call was a "great step forward" and the "right approach".
"What the IOC established is that quiet and discreet diplomacy gets you better than clashing cymbals," Pound, the IOC's longest-serving official, added.
"That's not the way you deal with any country, certainly not with China."
He added: "To accuse the IOC of being complicit with a Chinese propaganda effort built around Peng is complete nonsense."
Tennis player Peng, 35, disappeared from the public eye for almost three weeks after making the allegations, leading to sports stars and governments calling on China to provide proof that she was safe.
In a 1,600-word post on Chinese social media platform Weibo earlier this month, she said former Vice-Premier Zhang Gaoli - who is 75 - had "forced" her to have sexual relations with him.
Peng and Bach spoke for 30 minutes on a video call Sunday - her first public appearance since the allegations - and afterwards the IOC said she appeared safe and well.
However the Women's Tennis Association (WTA) said the call did not "alleviate or address" concerns about "her wellbeing and ability to communicate without censorship or coercion".
Human Rights Watch criticised the IOC over the video call, saying its "collaboration" with Chinese authorities on Peng's reappearance "undermines its expressed commitment to human rights, including the rights and safety of athletes".
The sporting rights organisation Global Athlete accused it of displaying "an abhorrent indifference to sexual violence and the well-being of female athletes".
Pound criticised the WTA's response, described it as "chest pushing".
He added: "First and foremost, a lot of people around the world were concerned that something might have happened to Peng.
"The IOC was the only organisation able to get through to her and alleviate some of those concerns.
"That was a great step forward, it's step one - you're not going to resolve the harassment allegations in the course of a 30-minute phone call without the other party being there but we know that she is well and healthy and seems in good spirits and is spending time with family and friends."
China has said the controversy surrounding Peng has been "maliciously hyped up".
