How it unfolded
In the spring of 1930, 28-year-old amateur Bobby Jones set out to win the four biggest tournaments of the year. In May he beat Roger Wethered 7 and 6 in the British Amateur at St Andrews; in June he won The Open at Hoylake at 291 and in July the U.S. Open at Interlachen at 287. The last hurdle was the U.S. Amateur in September on Merion's East Course. Jones medalist at 142 over 36 holes of qualifying and never looked troubled in match play. In the 36-hole final against New Jersey's Eugene Homans he was already well ahead at lunch and closed the match on the 29th hole, 8 and 7. More than 18,000 spectators packed the ropes so tightly the Marines had to clear a path. Jones announced his retirement that November and went on to build Augusta National and launch the Masters in 1934.
Why it still matters
No one has ever won the four majors of their era in one calendar year again. Jones's immediate retirement ended the era when an amateur could stand at the summit, and the professional Grand Slam structure that followed took root. What he left instead of prize money was Augusta National and the Masters — so the 1930 Grand Slam remains golf's most quoted and least repeatable feat.