Scott Blackmun, who was diagnosed with prostate cancer, faced stinging criticism for his handling of the case involving team doctor Larry Nassar.
Embattled United States Olympic Committee chief executive Scott Blackmun has stepped down following calls for his resignation in the wake of the USA gymnastics abuse scandal, it was confirmed on Wednesday.
Blackmun, who faced stinging criticism for his handling of the case involving team doctor Larry Nassar which rocked the sport, departs after eight years in the role.
The 60-year-old administrator had recently disclosed he was battling prostate cancer.
"Given Scott's current health situation, we have mutually agreed it is in the best interest of both Scott and the USOC that we identify new leadership so that we can immediately address the urgent initiatives ahead of us," USOC Chairman Larry Probst said in a statement.
"The USOC is at a critical point in its history. The important work that Scott started needs to continue and will require especially vigorous attention in light of Larry Nassar's decades-long abuse of athletes affiliated with USA Gymnastics."
USOC said board member Susanne Lyons would replace Blackmun as interim chief executive as the hunt for a permanent successor got underway.
Blackmun's departure comes after he had faced calls to resign for his alleged failure to act swiftly as the Nassar scandal unfolded, claims rejected by USOC.
Multiple US senators had demanded his resignation after a Wall Street Journal report that said USOC was made aware of allegations surrounding Nassar in 2015 yet did nothing to intervene.
USOC had defended Blackmun's handling of the case, with Probst telling reporters in Pyeongchang at the Winter Olympics this month that "he did what he was supposed to do and he did the right thing at every turn."
'They don't trust him'
Probst had initially ruled out any changes in personnel until an investigation ordered by USOC had determined who knew what and when, stating that Blackmun had "served USOC with distinction."
However, the progress of that investigation was confronted by an immediate roadblock after it emerged last week that several of Nassar's victims had vowed not to co-operate, citing mistrust of USOC and Blackmun.
The Wall Street Journal reported that Olympic gymnasts including gold medallists Aly Raisman and McKayla Maroney, had said they would opt out of the investigation.
"The athletes don't want to participate," a lawyer for the gymnasts told the paper. "They don't trust the USOC, and they don't trust (Blackmun)."
At least 265 female athletes, several of them Olympic gold medal gymnasts, claimed former US Olympic team doctor Nassar abused them over a period of two decades in the worst scandal in US Olympic history.
Nassar, 54, was last month sentenced to 40 to 175 years in prison for his crimes after days of harrowing victim-impact testimony.
Blackmun had issued an apology in the wake of those court hearings after USOC failed to send a representative to attend.