Check out these pros hitting with the Functional Tennis Saber as well as 2 of the world's best 10-year-olds Players 0:00 Wawrinka 0:35 Hurkacz 0:53 Karatsev 1:05 Djokovic (playing around with his son) 1:25 Panna Udvardy 1:41 Dayman Avramovski (2011) 🇧🇬 2:13 Rafael Pagonis (2011) 🇬🇷 Do you w...