"Guercilena has accepted the role of Team Manager of RadioShack Nissan Trek," a statement from the Luxembourg-based team read.
"Guercilena, currently sports director at RadioShack Nissan Trek, will overview the cohesion and continuity of the Luxembourgish cycling project that started two years ago.
"As of today Guercilena will be responsible for the organisation of the team and supervise all sports and technical operations."
Bruyneel, Lance Armstrong's team manager for the American's seven Tour de France wins, left RadioShack Nissan on Friday after being implicated in his former protege's doping scandal.
Bruyneel was named in the United States Anti-Doping Agency report released this week which said he was one of the people who had helped Armstrong organise doping within the US Postal Team.