On June 24, 2012, he finished 4th in the 400 meters at the 2012 United States Olympic Trials, a result that won him a position on the United States Olympic team as a member of the 4x400 relay. At the Olympics, Mance was part of the precarious American silver medal winning team. In the semi-finals, Mance took the baton from Manteo Mitchell after Mitchell completed half a lap with what turned out to be a broken leg. Mance helped pull the team back into position to qualify for the final. In the final, the winning Bahamas team stacked their team, putting their best, Chris Brown in the lead leg. Mance's second leg pulled the U.S. into contention while the two teams broke away from the field. Mance handed to Tony McQuay who ran a spectacular 43.4 split to take the lead. Mitchell's replacement, hurdler Angelo Taylor was out kicked in the last 50 meters by Ramon Miller to give Bahamas the win.