ALEXANDER ZVEREV, 22

World ranking: 5 Best Slam result: Q-finals (French Open, 2018, 2019) Best Wimbledon result: 4th round, 2017

The German has had a poor season, exiting the Australian Open in the last 16 and the French Open in the quarter-finals. His only ATP title of the year came in Geneva and the old question of whether he has the mental fortitude for two weeks of top-level tennis has only grown louder. He has the raw power but needs to up his serve-and-volley game to have any hope of reaching the last eight in London for the first time.

STEFANOS TSITSIPAS, 20

World ranking: 6 Best Slam result: S-finals (Australian Open, 2019) Best Wimbledon result: 4th round, 2018 He is the latest torchbearer of the next generation looking to end the hegemony of Novak Djokovic, Roger Federer and Rafael Nadal. But the talented Greek has never advanced beyond the last 16 at Wimbledon. He has beaten Federer and Nadal this year, but is yet to prove his mettle on grass.

FELIX AUGER-ALIASSIME, 18

World ranking: 21 Best Slam result: 1st round (US Open, 2018) Best Wimbledon result: Debut this year The Canadian, the youngest man in the top 100 who is mature beyond his years, is poised to be one of a handful of Next-Gen players with the tools to finally end the Big Three's stranglehold. His athleticism and technique and energy can trouble anyone. A string of impressive results, including three Tour-level finals and a long run at Miami, have moved him to a career-high world No. 21.

REUTERS