The world tennis number one is today playing fewer matches, entering less competitions and travelling to fewer countries each season compared to 20 years ago, according to research from William Hill.

Rafael Nadal, year-end world number one for 2019, played in just 60 ATP Tour matches last year and 13 ATP Tour tournaments while travelling to nine countries. In contrast, at the beginning of the millennium, the year-end world number one for 2000, Gustavo Kuerten, played 85 ATP Tour matches and participated in 22 ATP Tour competitions while jet-setting to 14 countries.

The year-end world number ones for 2001 and 2003, Lleyton Hewitt and Andy Roddick, racked up a massive 98 and 91 matches respectively in those years, while playing in 22 and 23 tournaments and travelling to 10 and 11 countries. Rafael Nadal and Novak Djokovic, meanwhile, played 78 and 65 matches in 2017 and 2018 respectively, and participated in 18 and 16 competitions as they visited 10 and nine countries each.

The decline in playing and travelling time across the past 20 years for the year-end world number ones has enabled them to free up more time for training, recovery and fine-tuning their bodies, allowing them to carry on deeper into their careers.

The world tennis number one today is able to play at the top of his game at a much older age compared to 20 years ago – Kuerten was 24 when year-end world number one in 2000, compared to Rafael Nadal at the end of 2019, who was 33.

Djokovic and Nadal were both 31 when year-end world number ones in 2018 and 2017 respectively, while in contrast, Hewitt was just 20 in 2001 and 21 in 2002, while Roddick was 21 in 2003.

As well as the evolution of the world number one involving less playing time and players going deeper into their careers, the playing style has also evolved.

The big service game at the turn of the millennium saw Kuerten hitting 742 aces and averaging 9.8 aces per match in 2000, with Roddick managing 989 aces and averaging 11.1 aces per match in 2003.

Compare that to recent years, where the power serve has been less prominent amongst the top players, with Nadal managing 271 aces and averaging 4.5 aces per match in 2019 and Djokovic hitting 342 aces and averaging 5.2 aces per match in 2018.

With the big power serve less of a focus for the world number one in recent years, they have landed more first serves while also winning more points on their second serve.

Kuerten and Hewitt landed 53.7% and 51% of their first serves in 2000 and 2002 respectively, while Nadal and Djokovic managed 68% and 66.2% in 2017 and 2018. Kuerten and Hewitt, meanwhile, won 53.7% and 54% of their second serve points in those years, with Nadal and Djokovic managing 61.2% and 56.6%.

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