In 1937 Metaxa won the Austrian national championships, defeating Roderich Menzel in the final. He played 16 matches for the Austrian Davis Cup team between 1933 and 1937, reaching the semifinal of the European zone in 1936. After the annexation of Austria into Nazi Germany in March 1938, Metaxa decided to join the German Davis Cup team for which he played 19 matches until the beginning of World War II. He was ranked the second best German player in 1938. In July 1938 he reached the final of the Wimbledon doubles competition with his partner Henner Henkel which they lost in four sets to the American duo Don Budge and Gene Mako.