The top tennis players tend to come in cycles. Right now the best tennis players in the world are either at the peak of their careers or nearing the end.
As a result, all of the top tennis players have been around for a while and have grown up before our eyes.
But at one point they were all teenagers just breaking into the sport. And while they are all recognizable as a teens, they all looked a lot different.
On the next few pages we'll take a look at how much the top tennis players have changed since their careers first started...
Novak Djokovic in 2005 (age 18)
Novak Djokovic now
Serena Williams in 1998 (age 16)
See the rest of the story at Business Insider
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