Thriller
Hall of Fame
There is no bigger advantage in tennis than serving lefty.
How? Lefties can target the returners backhand with the wide serve in the ad court. Righties have the same advantage in the deuce court.
Winning the first point of a game is the biggest predictor of winning the game and in the first point, the righty has the advantage over the lefty.
A textbook demonstration of this is Ashe vs Connors at Wimbledon 75, where Ashe used the sliding serve in the deuce court expertly to take Connors outside the court making for an easy put away volley.
However, it is indisputible that serving with your weaker throwing arm is a huge disadvantage.