Mia Lines is a stunning tennis player that is just four years old, but she’s getting instruction from the world’s top tennis coach–the coach of world-renowned players like Capriati, Roddick, Venus, and Serena. Her coach, Rick Macci, think’s that he has a heavy hitter on his hands in her little pint-sized body. Watch her story and see what you think.

Image Credit(s): Youtube