In 1966, Nicklaus won the Masters Tournament for the second year in a row, becoming the first golfer to achieve this, and also won The Open Championship, completing his career slam of major championships. At age 26, he became the youngest to do so at the time.In 1968 and 1969, Nicklaus did not win a major tournament.ore at http://sports.quickfound.net. On April 11, 1966, Jack Nicklaus wins the 1966 Masters Tournament at Augusta National Golf Club in a playoff with Tommy Jacobs and Gay Brewer, becoming the first in history to win the title two years in a row. From Universal Newsreel Volume 39, Release 31, April 14, 1966.