Sentence:  After playing a splendid first nine holes in 34 - two strokes under par - on this fifth and final day of the tournament ( Sunday 's fourth round had been washed out by a violent rainstorm when it was only half completed ) , Player 's game rapidly <WSD>fell</WSD> to pieces . 
Meaning of the word marked with <WSD> tags:  pass suddenly and passively into a state of body or mind