Following the outbreak of World War II, as soon as he reached the legal age Mangurian enlisted in the United States Navy.
Following his discharge, Mangurian returned home to work in the family's retail furniture business which he would build into a national chain.
At the end of the 1978 season, by which point he had effectively dismantled the team in a successful effort to break the Braves' lease on the Aud, he and his partner John Y.
After one season, Mangurian bought out Brown and as the franchise's owner saw the Celtics sign stars Larry Bird, Kevin McHale and Robert Parish.
[2] Mangurian also became involved with the North American Soccer League (NASL) as part of the ownership of the Memphis Rogues.
In 2002, he received the national Eclipse Award of Merit, the American Thoroughbred horse racing industry's highest honor.