In golf, in your opinion, what is the biggest meltdown in Major Championship history?

QUESTION:
Out of the U.S. Open, Masters, British Open, and P.G.A. Championship, what do you think is the biggest meltdown in major golf championship history?

ANSWER:

Answer by mbl
There have too many for me to choose one. Van de Velde comes to mind but that was just one hole and one VERY bad bounce. Roberto signing a wrong card at the Masters deserves a mention. Just last year, Kenny Perry was on cruise control until the final 2 holes and the playoff. Gil Morgan got it to 12 under at the 92 Us Open only to finish well over par. It all comes down to ones precise definition of meltdown.