Grand Slam champions share thoughts on Sharapova's return.
The 21-year-old Aussie is happy with his new fitness trainer, but not ready for a coach.
The new energy bar is energizing the tennis community.
Haas invoked fear factor on Federer.
Hall of Famer on why "quiet please" is vital for elite players.
"I will look to play maybe a couple of exhibition events leading up to my first tournament in April," Sharapova said.
World No. 5 offers revealing answer on happiness.
