In certain sports, left-handedness is advantageous. For example, in baseball, where right-handed pitchers greatly outnumber left-handed pitchers, it is commonly known that a left-handed batter is more successful against right-handed pitchers than a right-handed batter. In fact, a lot of strategy is used, such as bringing in a relief pitcher to have an advantage over a certain batter, effectively to get a much needed out.
In ice hockey, there are many more left-handed shooters, and the majority of goaltenders catch with their left hand, forcing opponents to shoot left-handed.
In one-on-one sports, like fencing, boxing, tennis and table tennis, left-handers have an advantage because they are accustomed to playing against a right-hander. Right-handers have less opportunities to play against left-handers and can be thrown off mentally and tactically.
Rafael Nadal, formerly a world number one ranked tennis player who has won eleven Grand Slam singles titles, went from playing tennis with his right hand to his left hand at age 8. At age 19, Nadal won the French Open title. It was the first time he had played in the event.
Sandy’s year long journey – going from being a right-hander to left-hander, and Kelly’s parallel trip as a left-hander doing things as a right-hander.