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|Venue: All England Club, Wimbledon Dates: 2-15 July|
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There are unfamiliar names in the Wimbledon men's semi-final line-up, but there remains a familiar theme - an absence of young players.
The wait for a Grand Slam winner born in the 1990s goes on, with Rafael Nadal, 32, Novak Djokovic, 31, Kevin Anderson, 32 and John Isner, 33 flying the flag for the old brigade on Friday.
Looking at the record books, Swiss player Stan Wawrinka is the only player since 2001 who was older than 25 when he won his first Grand Slam. Roger Federer, Nadal and Djokovic were under 22 when they won their first majors. World number seven Dominic Thiem, 24, came close in May when he lost to 'King of Clay' Nadal in the French Open final.
So why have the next generation not broken through? Do they apply themselves like the more experienced players? Are we experiencing a freak period in men's tennis?
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'Zverev could be the one'
Richard Krajicek was a promising young talent who did realise his potential, winning Wimbledon in 1996 at the age of 24.
The 6ft 5in Dutchman, who fired down serves over 120mph, told BBC Sport that top 20 players like German Alexander Zverev, Austrian Thiem and Australian Nick Kyrgios might have to wait until the dominant pack lay down their racquets.
"The top dogs still play great tennis," said the 46-year-old, who won 17 ATP titles during a 14-year career.
"I hope for the sake of Zverev and Kyrgios that they give up - the old guys are playing amazing tennis, especially in the Slams.
"After he reached this year's Rome Masters final, I thought that Zverev could do it at the French Open, but sadly three five-set matches took it out of him at Roland Garros.
"That experience will help him in the future though. Zverev could win a Slam, but in the near future it's the current three or four regular winners who will continue to rule."
'Kyrgios has to step up'
ATP's 2015 Star of Tomorrow, Zverev, is its big young star of today, now third in the world rankings. Aside from Krajicek, former players Mark Philippoussis and Fabrice Santoro also told BBC Sport that they think the German is the most likely to break past the old guard.
Australian Philippoussis was less sanguine about the prospects of his compatriot Kyrgios.
The 23-year-old world number 18 was recently labelled as "pathetic" by former Wimbledon women's singles champion Marion Bartoli, who added that he had not grown up. In response, Kyrgios told the Frenchwoman to "stop assuming".
Kyrgios has won four senior titles, but also has a catalogue of misdemeanours - last month he was fined 15,000 euros (£13,278) for making a lewd gesture while sat courtside at the Fever-Tree Championships at Queen's Club. He was knocked out at the last-32 stage at Wimbledon, and has yet to go further than the last eight at a Grand Slam.
Philippoussis, 41, said: "He's part of the next generation, but he'll have to step up.
"He's got all the talent in the world, but has to improve the other things. Someone like Zverev has the whole package.
"The mind is very important - he has to be strong mentally and physically and then get on the pathway."
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'The level above is just a lot better'
Could it be the case that the next generation do not apply themselves in the same way as the multiple Grand Slam winners?
"The youngsters are coming but it'll take a while," said former top-20 player Santoro, who has coached two-time Wimbledon semi-finalist Richard Gasquet.
"We have some good young players - but they are yet to win a big title. There is no specific explanation, it's just that the best four or five players are too good.
"Players like Thiem and Zverev, they want to win Slams. It's not a question of their mentality and ambition, it's just the level above is a lot better."