Alexander Zverev, Nick Kyrgios, Grigor Dimitrov and Lleyton Hewitt took to the court on Monday at Sydney's Ken Rosewall Arena for the Fast4 Showdown exhibition.
Fast4 adjusts the rules of tennis with abbreviated sets, no-ad scoring and no let calls. Additionally, the server can call a "Power Play" once per set, making the next point worth twice as much on the scoreboard.