Leius was the boys' singles champion at the
1959 Wimbledon Championships. He won the
Soviet Championships in 1963, 1964, 1965 and 1968. He also won the
Moscow International Indoor Championships five times from 1961 to 1963, 1965, 1969. Other good performances during his career include reaching the final of the 1964
Queen's Club Championships, which he lost to
Roy Emerson, and taking
Rod Laver to five sets at the
1969 Heineken Open. He was a gold medalist in the mixed doubles at the
1970 Summer Universiade in
Turin, with
Tiiu Parmas. His best performance in the singles draw of a
Grand Slam tournament came at the
1965 French Championships, where he made the quarter-finals. He was due to face South African player
Cliff Drysdale in the quarter-final but the Soviet delegation made him forfeit the match, in protest against
apartheid. Leius and
Winnie Shaw were mixed doubles runners-up at the
1971 French Open. He was a regular fixture in the Soviet
Davis Cup team during the 1960s and appeared in a total of 20 ties, from which he managed 23 wins, 17 of them in singles. ==Murder conviction and prison==