U.S. boxing coach Dan Campbell retired Friday after his attempt to remake the American team backfired in Beijing with its worst showing in Olympic history.

Campbell, a 65-year-old veteran of the amateur boxing ranks in Virginia Beach, Va., had been the national director of coaching for USA Boxing since 2005.

He was in charge of the nine American fighters in Beijing, winning just one medal. The U.S. team hadn't left the Olympics with fewer than two medals since 1948, when it won one silver.

Heavyweight Deontay Wilder's bronze was the only prize for the U.S. program, which has won but one gold medal in the last three games.

"We all share the disappointment of our team's performance in China, and look forward to establishing a fresh start for our coaching program in advance of London," USA Boxing chief executive Jim Millman said.

Campbell didn't immediately return a phone call.

He spent the last year under heavy criticism from inside and outside the team, primarily for his decision to institute a residency training program that confined U.S. boxers to Colorado Springs for most of the last year.

Campbell wanted to prepare his fighters for the international style of boxing with specific coaching and training methods. The fighters complained about the exclusion of personal coaches and travel restrictions that kept them from family and friends.

At least two fighters _ Luis Yanez and Javier Molina _ left the team for extended periods without permission. Yanez was kicked off the team for three weeks in July after failing to show up for most of June.

World champions Demetrius Andrade and Rau'shee Warren were upset early in Beijing, and bantamweight medal hopeful Gary Russell Jr. didn't even compete after failing to make weight before the games. Wilder won two fights to qualify for a bronze medal but was soundly beaten by Italian world champion Clemente Russo.

Yanez openly criticized Campbell's coaching and discipline during the summer, telling The Associated Press he would refuse to listen to Campbell during his fights in Beijing. Yanez, whom Campbell called "one of the biggest liars I've ever met," then openly ignored Campbell's coaching in his second-round loss to Mongolia's Serdamba Purevdorj.

Millman plans changes for the U.S. team's approach to the 2012 London Games. He intends to involve the fighters' personal coaches to a greater degree, although he hasn't said if the residency program will be reinstated.