Reaching the top of the junior tennis world should indicate a player is on the path to tennis stardom — but there's a reason why that isn't the case.

Margaret Court and Novak Djokovic played in two different tennis eras that were a world apart. Both were champions of their time and won 24 grand slam titles. Djokovic is aiming for more.

World No.2 Alexander Zverev has flown under the radar but can't avoid the spotlight playing 10-time Australian Open champ Novak Djokovic in the semi-finals.