The U.S. lost for the first time in World League play Saturday at Hoffman Estates, Ill., 26-24, 25-17, 14-25, 13-25, 15-12.
Kawika Shoji started the match, played first two sets. Micah Christenson came in for the final three sets.
Erik Shoji at libero.
U.S. drops to 7-1, Bulgaria 1-7.
Americans head to Russia for matches June 27-28. The need one more win to qualify for the final round in Italy.