RECORD numbers of men over the age of 30 have been competing in grand slam tournaments this year, but at the same time a new wave of younger players have been making huge strides.
The Independent's Paul Newman looks at nine of them ahead of Wimbledon, which starts on Monday.
Dominic Thiem (Austria, aged 22, world No.8)
Had outstanding clay-court season. Won title in Nice, was runner-up in Munich, beat Roger Federer in Rome and reached semi-finals at French Open before losing to Novak Djokovic. Has maintained his form on grass, winning title in Stuttgart (where he beat Federer again) and making semi-finals in Halle (where he lost to eventual champion Florian Mayer). Has won four titles this year and is only man to win tour titles in 2016 on three different surfaces.
Nick Kyrgios (Australia, aged 21, world No.18)
Hugely gifted player who has often attracted adverse publicity with his controversial behaviour and language but has worked hard at his game this year. Won his first title in Marseilles in February. Reached Wimbledon quarter-finals on his debut as world No 144 two years ago after beating Rafael Nadal, then world No 1. Made fourth round last year before losing to Richard Gasquet.
Alexander Zverev (Germany, aged 19, world No.28)
Arguably the most exciting teenager in men's tennis. Stands 6ft 6in tall and has game to match his imposing frame. Beat Federer at Halle last week before losing to fellow countryman Mayer in final. Reached his first final in Nice last month, losing to Dominic Thiem. Broke into world's top 100 only 13 months ago. Works with Jez Green, Andy Murray's former fitness coach.
Lucas Pouille (France, aged 22, world No.29)
Latest in a long line of talented Frenchmen. Currently at career-high position in world rankings after making major progress on clay with wins over Richard Gasquet, Ivo Karlovic, David Goffin, David Ferrer and Juan Monaco. Lost to Murray in semi-finals of Rome Masters. Lost to Kevin Anderson in only previous match at Wimbledon last summer.
Borna Coric (Croatia, aged 19, world No.49)
Made headline-grabbing start to career on main tour with victories over Nadal and Murray but is currently 16 places below career-high position he reached 11 months ago. Has yet to win a title but has lost in two finals this year, at Chennai and Marrakech. Won his first match at Wimbledon last summer and has twice reached third round of French Open. Coached by Miles Maclagan, who used to work with Murray.
Taylor Fritz (US, aged 18, world No.63)
Was ranked No 761 in the world at this stage last year but has since made massive strides. Reached his first tour final before losing to Kei Nishikori at Memphis in February and took a set off Federer on grass at Stuttgart earlier this month. Based in Carson, California, where he is coached by David Nainkin and Christian Groh.
Jiri Vesely (Czech Republic, aged 22, world No.64)
First broke into world's top 100 three years ago and won his first title in Auckland at start of last year but progress has stalled in recent times. Nevertheless, enjoyed biggest win of career by beating Novak Djokovic in Monte Carlo Masters two months ago. At 6ft 6in tall has the ideal build for success in modern game.
Kyle Edmund (GB, aged 21, world No.68)
Has been at his best on clay in the past - his only two victories at Grand Slam tournaments have been at the French Open - but has shown good form on grass in recent weeks. Reached quarter-finals of Aegon Championships at Queen's Club last week before losing to Murray and beat Lukas Rosol in Nottingham this week. Currently at career-high position in world rankings.
Jordan Thompson (Australia, aged 22, world No.91)
Broke into top 100 earlier this year and has won two Challenger tournaments in 2016. Won his first Grand Slam match at this year's French Open, having qualified for a Grand Slam tournament by dint of his world ranking for the first time. Will play doubles at Wimbledon with Lleyton Hewitt, Australia's Davis Cup captain.
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