 Spencer was a competent feather and lightweight who would fight top talent in his career, including world jr. lightweight champion Jack Bernstein, top rated feather and lightweight contender Benny Valgar, and world featherweight champion Johnny Dundee.Mosberg lost to his friend, highly rated lightweight contender, Mel Coogan on August 13, 1921, before a large crowd at Long Island's Queensboro Stadium in a twelve-round points decision.Coogan, who had risen in the ranks to a well-rated lightweight contender, beat his old friend easily, though he knew his style and technique from their years of coaching navy boxers together in World War I.