Many professional footballers, tennis players, baseballers incorporate a medicine ball into their plyometric strength training.
Free weights such medicine balls are more popular due to the bigger emphasis on compound exercises, core strength and training with movements that mirror the movements of thesport.
Hucking, pulling and catching are three of the actions which benefit greatly from upper body core strength. I want to train with something more specific than a medicine ball - I want a medicine disc.
Basically a disc that is about 3-5 times heavier than a 175g ultrastar. But can still be held comfortably in a backhand grip.
You can practise your pulling, pivoting and catching with it. Come game time, a 175g disc will be a piece of cake.