The 54-year-old motivational speaker raises awareness about people with disabilities by wowing baseball fans and throwing out a ceremonial first pitch with his feet.
Willis hopes to throw a first pitch at all 30 Major League ballparks. Thus far he's made it to 22.
As Willis gets closer to his goal, footage of his first pitches have gone viral, with his latest appearance coming at Thursday's Royals/Twins game at Kauffman Stadium in Kansas City.
"Basically, I hold the ball with my right foot and step back with my left leg," Willis explained after throwing a first pitch for his hometown San Diego Padres in 2011.
"Then I lift my left leg into a kick like a real pitcher does. I bring that leg down slowly and the right leg comes up. Using the momentum that I've created in my hips when I bring my left foot forward, I get an extra whip and just try to throw straight at the catcher with the ball coming from my right foot. Most times it gets there. It's similar to the same way people throw with their arms, but I do it with my legs and feet."