During World War II he continued to win prizes in the United States , since the war had effectively put an end to international tennis .
During World War II he did not compete in the U.S. Championships in 1944 and 1945 .
During World War II he continued to win prizes in the United States , since the war had effectively put an end to international tennis , but did not compete in the U.S. Championships in 1944 and 1945 .