Whoever said that "The Masters doesn't really begin until the second nine on Sunday" really knew his stuff. The previous three and a half rounds serve to get you to the tee on 10. By that time, you are exhausted if nothing else. Augusta is brutally steep - equivalent to a 15-story building from the clubhouse to the green on 12. It doesn't show well on TV, but every fairway is steep and slanted. Just walking the course is a challenge (how the caddies do it is beyond me.) And you do that climb/descend twice each round. Part of the reason pros take so long over a shot is just to get their heart rate and breathing back to nearly normal.
