United States Olympic Committee (USOC) chairman Larry Probst will step down at the end of the year, announced the organization, which has faced criticism of its handling of sexual abuse scandals.
Probst will be replaced by Susanne Lyons, an independent USOC board member who until last month served as the USOC's acting chief executive officer.
Lyons, who will begin a four-year term as chairman on January 1, 2019, was replaced as USOC chief executive last month by Sarah Hirshland.
"We will do everything to regain the trust of our entire athlete community, especially those survivors of recent sexual abuse scandals," Lyons said.
Former US gymnastics national team physician Larry Nassar is serving what amounts to a life sentence behind bars after pleading guilty to sexual abuse charges, with more than 350 women and girls said they were abused by Nassar.
Other abuse scandals involving swimmers and taekwondo athletes have prompted investigations with the USOC agreeing to full cooperation.
"We failed our athletes," Probst said. "I'm at the top of the food chain so I take this very personally. We're very sorry for what happened. We're very empathic to our survivors."
Probst said it was "an ideal time" to leave given Hirshland's taking charge and the chance to keep Lyons in a top job, the change in leadership to two women leaders a signal of a change in culture to make athletes a higher priority.
"We have to remember they are the center of our universe," Probst said. "There does need to be a cultural change. I think they will drive the culture in a positive direction and I couldnt be happier with the team we're putting into place."
Probst said he will meet with IOC President Thomas Bach in a couple weeks in New York to see about future Olympic-related opportunities.
"We've agreed to get together and see if there is some role for me in the Olympic movement," Probst said. "I want to try to stay connected in some way. I'm not moving to Mars."
- 'Challenging time' -
Lyons said she wanted to stress that athletes and their safety were a greater priority than money or medals even as the USOC tries to address all areas to fulfil its mission.
"I'm honored that the board has entrusted me with this position, eager to continue to support our athletes and ready to do the work necessary to regain the trust of our athlete community," Lyons said.
"The USOC is at critically challenging time in its history and we simply must get it right. I intend to make sure we do."
Lyons said she wants to ensure as chairman that leaders are hearing the concerns of athletes.
"Our work to provide advice and strategic direction and be aware and hear the athletes' voice much stronger," she said.
"Change is good and I think there are some areas where we need change going forward," Lyons said. "That has to start with the board and with Sarah."
Probst served three four-year terms in the position, helping improve relations with the International Olympic Committee and boosting sponsorship deals.