"As much as I train on the court, off the court and in the gym, nutrition is absolutely everything to my performance,” Isner said. “I want to play professional tennis as long as I can, which means I need to take care of my body in all the right ways. I have this same mindset when it comes to my dog Magill, which is why I decided to partner with Nulo. Six years from now, I want him to be running on the tennis court, chasing balls the same way he is today.”