Serena Williams serving during the 2019 Australian Open. (Getty Images)

The serve is the most important shot in tennis. It's the only shot a player has complete control of hitting, and it sets the tone for every point. If you have a great serve, it will take you far, no matter how good the rest of your game is.

On both the ATP and WTA tours, there are many great servers, who slam ace after ace and place their shots with impeccable accuracy. But who is the best server in tennis, outshining the rest with power and precision?