Wawrinka-Simon; How Wawrinka Got in to the Zone in the Fifth Set

How did Stanislas Wawrinka of Switzerland find the zone down 2 sets to 1 and 1-3 in the fourth? Gilles Simon of France was riding the home crowd energy and pushing toward the finish line. However, Wawrinka found another gear and eventually won the match going away in the fifth set.

For much of this match Wawrinka dictated the outcome of the points having far more winners and unforced errors (in fact 82 winners to Simon's 23, and 88 unforced errors to Simon's 49). Gilles Simon attempted to play more aggressive and finish points by coming forward, but the "easy power" of Wawrinka allowed him to control the court. In particular his backhand down the line punished Simon time and time again.