Daily Data Viz: ATP's returning friends, new blood on tour in 2015

While 2015 began with common names at the top of the ATP rankings -- Novak Djokovic, Roger Federer and Rafael Nadal -- we also saw two new Grand Slam winners

While 2015 began with common names at the top of the ATP rankings -- Novak Djokovic, Roger Federer and Rafael Nadal -- we also saw two new Grand Slam winners enter the picture in 2014. Take a look below to see how the age of Slam winners has changed since the top three men won their first Slams.

Check SI.com's Australian Open Daily Data Visualizations hub page throughout the whole tournament for the latest data-driven infographics and charts.