What a difference a year makes.
Last year, the great Roger Federer won his 17th Grand Slam title. This year, he dropped out of the Top Five.
Andy Murray became a national hero. Novak Djokovic looked less than invincible, and Rafael Nadal looked unstoppable.
Yet only Nadal and Williams will finish the year with more than one Grand Slam title. They also seem likely to finish the calendar year ranked No. 1.
Although there is plenty of tennis left to play in 2013, the Grand Slams are finished.
Let's face it, Grand Slams define careers.
How the top stars perform in Slams determines how the public perceives them.
So how did their performances in 2013 impact public perception?