The phrase "to block the shot" means stopping or obstructing someone from successfully making a shot in a sport, especially in games like basketball or soccer. Full definition
My rookie year I was leading the league in blocked shots and shooting 51 % after 17 games, when my foot went out. (si.com)
She out rebounds, and blocks the shots of boys her age on a regular basis. (religion.blogs.cnn.com)
More over a naturally right footed player will use his right foot to block the shot if it coming from the right, and more so if he is short. (justarsenal.com)