Since 1962 Koch has played tennis on an international level with amateur status. From 1968 until his retirement he was active as a tennis professional. He won 14 titles in singles and three tournaments in doubles, including all titles from his amateur and professional career.
One of his greatest successes is the victory in the mixed competition of the French Open 1975 , which he won with Fiorella Bonicelli (Uruguay). In the final they defeated the duo Pam Teeguarden and Jaime Fillol in two sets with 6: 4 and 7: 6.
Between 1962 and 1981 he played 44 games for the Brazilian Davis Cup team . He holds most of the team's records, including most appearances and most wins.
Brazil
