Roger Federer, of the silken one-handed backhand fame, has had a slew of records and landmark moments during his record-breaking 21-year tennis career.
On 22nd September 1997, a 16-year-old precocious Federer first entered the ATP singles rankings at no. 803 after scoring 12 points at Switzerland 1 Masters Satellites at Bossonnens.
Amongst active players, only Feliciano Lopez and Ivo Karlovic have had a singles ranking for a longer period.
The Swiss has been ranked in the top ten for 872 weeks (733 uninterrupted) - the most by any player in the Open Era - and has had a staggering reign of 237 consecutive weeks at no. 1. He is also the oldest top-ranked player (36 years, following 2018 Rotterdam).
The epitome of sustained excellence and longevity, Federer is the oldest player in the top 50 (as on 5th August 2019) and the oldest to win Wimbledon (35 years 11 months at 2017 Wimbledon).
Among shared records, he is one of 26 players to be ranked world no. 1, one of only 8 players to have won the career Grand Slam, one of only 6 players to have won 10 or more Masters 1000 titles and one of only 2 players to have 200 match wins over top 10 opposition.
Only Rafael Nadal (34) and Novak Djokovic (33) have more Masters 1000 titles than Federer (28).
Along with American Jimmy Connors, Federer is the only player to register 1200 singles match wins and 100 career singles titles. His 733 consecutive weeks inside the top ten is only bettered by arch-rival Rafael Nadal (745 and counting as on 5th August 2019).

However, the Swiss has a plethora of records and landmarks where he stands alone.
Here's presenting Federer's 38 standalone records on the occasion of the Swiss maestro's 38th birthday.
Happy Birthday, Roger!
#38 to #27
#38: Most wins over top ten opposition (221).
#37: Most match wins on grass (187).
#36: Most grass-court titles (19).

#35: Won 24 consecutive tournament finals (2003 Vienna to 2005 Basel)
#34: 310 weeks as world no. 1.
#33: 237 consecutive weeks as the world's top-ranked player.
#32: Oldest player (36 years) to become world no. 1 following his 2018 Rotterdam title.
#31: 850 weeks ranked inside the top ten (872 weeks as on 5th August 2019)
#30: Most defeats in Masters 1000 finals (22).

#29: Most finals at a tournament (14 - Basel).
#28: Won 6 titles at the season-ending ATP Tour Finals.

#27: 100 match wins at a single tournament (Wimbledon).

#26 to #14:

#26: Won 10 titles on 3 different surfaces (Hard Court - 70, Grass - 19, Clay - 11).
#25: 30 consecutive sets won at the Australian Open (2006-08).
#24: 34 consecutive sets won at Wimbledon (2 separate occasions: 2005-06, 2017-18).
#23: 40 consecutive matches won at Wimbledon (2003-2008).
#22: 40 consecutive matches won at US Open (2004-2009).
#21: Most match wins at the Australian Open (97).

#20: Most match wins at Wimbledon (101).

#19: Reached 5 finals at all the 4 Grand Slams (Australian Open - 7, French Open - 5, Wimbledon - 12, US Open - 7).
#18: Reached 7 finals at two different Grand Slams (US Open and Australian Open).
#17: Reached 10 consecutive Grand Slam finals (2005 Wimbledon to 2007 US Open).
#16: Reached 23 consecutive Grand Slam semifinals (2004 Wimbledon to 2010 Australian Open).
#15: Reached 36 consecutive Grand Slam quarterfinals (2004 Wimbledon to 2013 French Open).
#14: Reached all 4 Grand Slam finals in a calendar year on 3 occasions (2006, 2007, 2009).
#13 to #1:

#13: Most appearances in a Grand Slam singles draw (77).
#12: Most Grand Slam singles quarterfinals (55).
#11: Most Grand Slam singles semifinals (45).
#10: Most Grand Slam singles finals (31).
#9: Played 400 Grand Slam matches (410 as of 2019 Wimbledon).
#8: Won 70 matches at each of the 4 Grand Slams (Australian Open - 97, French Open - 70, Wimbledon - 101, US Open - 85).
#7: Won 350 Grand Slam singles matches (353 following 2019 Wimbledon).

#6: Won 11 hard court Grand Slams (6 - Australian Open, 5 - US Open).
#5: Won 3 Grand Slams in a calendar year on 3 occasions (2004, 2006, 2007).
#4: Won his first 7 Grand Slam singles finals (2003 Wimbledon, 2004 Australian Open, 2004 Wimbledon, 2004 US Open, 2005 Wimbledon, 2005 US Open and 2006 Australian Open).
#3: Won two consecutive Grand Slam tournaments 5 times (Wimbledon, US Open).
#2: Won 8 Wimbledon singles titles
#1: Won 20 Grand Slam singles titles.

Happy 38th Birthday Roger!
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