What was odd about Bob Goalby's 1968 win at the Masters?

Question

The American won by one stroke, but what was unusual about his victory?

Answer 1

Goalby only won because Roberto De Vicenzo, who who finished tied for the lead, signed an incorrect scorecard. He was penalized and dropped out of the playoff, giving the Masters victory to Goalby. De Vicenzo never won another major, though the year before in 1967 he'd won the Open.