Worst Collapses in Major Championship History

Adam Scott, 2012 British Open
Scott led by four shots entering the final round at Royal Lytham and St. Annes and appeared ready to win his first career major championship. He also led by four shots with four holes to play, but then it happened: he closed with four straight bogeys, capped by a missed par putt on 18 (above) that would've gotten him into a playoff. Ernie Els shot a final-round 68 -- including a birdie on 18 -- to win by one shot.