None, since 1973 we only have 7 players with 33+ years old who were in the Top 10. Rosewall, Laver, Ashe, Connors, Lendl, Agassi and Federer. The only one who has a good shot it is Djokovic but I don't think so
Good listing of those top players with longevity, I'll elaborate a bit below.
According to ATP rankings (starting 1973...)
Ken Rosewall -
Longevity King (OE) -
#9 at age 41 in June '76 (He turned 42 later in the year, was #13 at year's end)
Rod Laver -
Grand Slam King (2) -
#10 at age 37 in December '75.
Arthur Ashe -
Humanitarian King -
#7 at age 36 in December '79.
Jimmy Connors -
Title King -
#10 at age 36 in April '89, top 20 until Feb '90.
Andre Agassi -
Return King -
#10 at age 35 11+ months in April 2006.
*Roger Federer -
King - certain to be
#2 at age 33 and 5+ months in Jan 2014.
Ivan Lendl -
Masters King -
#7 at age 33 and 5 months in August '93.
*Still active
+Note that Richard "Pancho" Gonzales, another Longevity King, was considered world #6 in 1969 (prior to ATP rankings) at the age of 41 and was still capable of beating world #1 Laver a year later, and 3 months short of his 44th birthday in 1972 won his last title.
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Given the longevity of those great top players mentioned, why the "None" conclusion?
Is the quality of the youngest players such that the top quality older ones will be replaced in 5 years?
Injury may take it's toll on some who are the most prone, sure.
Age and Motivation on others, maybe.
Is it unreasonable to say 2 or 3 of the 6 slam winners in the current top 10 might be in the top in 5 years? Granted it is obviously almost impossible to say with any certainty. It's a just for fun thread anyway, which hopefully will be most fun to read in 5 years.
Curiously, Roger Federer was World #1 in 2005 and five years later in 2010, and now five years later in 2015, has a chance to be #1 again. That's appr. 3 generations of players at the top. Who would have predicted that?
In 1995, 3 repeated, in 2000, the top 2 repeated, in 2005, only the #1 Agassi, and he was a 3-peat, in 2010, only the top 2 from 2005 repeated. In 2015, the top 4 repeated, and one, Federer was a 3-peat.
Given his age and lack of serious injuries and flexibility, I think Mr. Novak Djokovic has a solid chance of repeating again unless motivation wanes. I won't write Mr. Federer off until he decides to hang up his racquet. Mr. Nadal might extend his career by playing 40-60 matches/year. Mr. Del Potro is still young and has missed about 2 years and if he isn't in an injured phase, could be there in 2020, given his quality.
Repeat - Three-peat
Jan 1, 1995....................................
Jan 1, 2000....................................
Jan 1, 2005.....................................
Jan 1, 2010........................................
Jan 1, 2015
01 Sampras, Pete (USA....................01 Agassi, Andre (USA)....................01 Federer, Roger (SUI).....................01 Federer, Roger (SUI).......................01 Djokovic, Novak (SRB)
02 Agassi, Andre (USA)....................02 Kafelnikov, Yevgeny (RUS)...........02 Roddick, Andy (USA).....................02 Nadal, Rafael (ESP).........................02 Federer, Roger (SUI)
03 Becker, Boris (GER)......................03 Sampras, Pete (USA)..................03 Hewitt, Lleyton (AUS)...................03 Djokovic, Novak (SRB).....................03 Nadal, Rafael (ESP)
04 Bruguera, Sergi (ESP).................04 Enqvist, Thomas (SWE)...............04 Safin, Marat (RUS)........................04 Murray, Andy (GBR).........................04 Wawrinka, Stan (SUI
05 Ivanisevic, Goran (CRO)..............05 Kuerten, Gustavo (BRA)..............05 Moya, Carlos (ESP).......................05 Del Potro, Juan Martin.....................05 Nishikori, Kei (JPN)
06 Chang, Michael (USA)..................06 Kiefer, Nicolas (GER)....................06 Henman, Tim (GBR).......................06 Davydenko, Nikolay (RUS)..............06 Murray, Andy (GBR)
07 Edberg, Stefan (SWE).................07 Martin, Todd (USA)......................07 Coria, Guillermo (ARG)..................07 Roddick, Andy (USA)........................07 Berdych, Tomas (CZE)
08 Berasategui, Alberto (ESP)..........08 Lapentti, Nicolas (ECU)...............08 Agassi, Andre (USA).....................08 Soderling, Robin (SWE)...................08 Raonic, Milos (CAN)
09 Stich, Michael (GER).....................09 Rios, Marcelo (CHI).....................09 Nalbandian, David (ARG)..............09 Verdasco, Fernando (ESP)...............09 Cilic, Marin (CRO)
10 Martin, Todd (USA)......................10 Krajicek, Richard (NED)...............10 Gaudio, Gaston (ARG)...................10 Tsonga, Jo-Wilfried (FRA).................10 Ferrer, David (ESP)
Agassi #8 in 1990, not a slam winner yet, but 2 slam finals in 1990, with 1st slam in '92.
Becker #2 in 1990
Chang #6 in 1990
Edberg #3 in 1990
Respectfully,
masterclass