Flashback to 20 July 2015, and you find 18-year-old Alexander Zverev No. 123 in the Emirates ATP Rankings. His potential was obvious but yet to be fully realised.

Fast forward two years to 31 July 2017, and you discover that the now 20-year-old German has skyrocketed to No. 8 in the world. He is now the real deal, and what’s scary is that his potential is still largely unearthed. He is still adding muscle to his 6’6” frame, still putting the subtleties of strategy together, and still discovering what really matters when push comes to shove under the bright lights.

Look out world when this jigsaw comes together. The discussion about Zverev rising to No. 1 in the world is largely about when – not if.

An Infosys ATP Beyond The Numbers analysis of his rapid rise up the Emirates ATP Rankings since the beginning of the 2015 season uncovers a player who is improving in all areas of his game, but especially making the most of his opportunities when he gets ahead in the score when returning.

Percentage Breaking Serve From Specific Point Scores

As a natural result of his improved return game, Zverev is ranked third on tour in 2017 in converting break points, at 46 per cent (141/347). That’s better than recognised returners such as Novak Djokovic (45 per cent), Kei Nishikori (44 per cent), Rafael Nadal (42 per cent) and Roger Federer (41 per cent).

These numbers are significant on a number of levels, but particularly because a player of Zverev's height (6’6”) is naturally suited to be more proficient serving than returning. He is basically just as good at both.

Zverev is 15th on the ATP Stats Serve LEADERBOARD, powered by Infosys Nia Data, during the past 52 weeks, and 18th returning. Only Federer and Nadal place in the Top 20 in both categories in 2017. That’s the kind of company Zverev is keeping and how well rounded his game really is.

What’s also fascinating is that Zverev’s improved return metrics in 2017 over the previous two years are coming against much tougher opposition standing on the other side of the net. His average opponent rating this season is less than half of what it was in 2015, but he is putting up stronger numbers across the board.

Alexander Zverev – Average Opponent Ranking

2017 = 49

2016 = 66

2015 = 130

The rest of the 2017 season is set to be a steep upward curve for Zverev’s game as well, since he has only 14 per cent of his points to defend for the rest of the year. Almost every tournament will be an opportunity to add points and keep climbing up through the Top 10.