33-year-old Nadal has once again defied expectation, bouncing back stronger than ever from a series of injuries that continue to threaten his dominance, and continue to fail.
And as he season ends with a Davis Cup, added to French and US open titles and a year-end world No. 1 spot, there's a strong case that this may be his finest year ever.
WHAT THEY SAY - 'His ability to improve has been amazing'
Feliciano Lopez, Nadal's doubles partner during Spain's Davis Cup victory, believes Nadal is on top of the tennis world right now.
"Rafa (Nadal) is so competitive," said Lopez. "He kept me in the doubles match on Saturday, he had a tremendous adrenaline and in the second set I was worse, he was still supporting me, giving me the strength I needed, being focused.
"You suffer a lot. He is the number one on all aspects."
His coach Carlos Moya agrees that Nadal has had a near perfect experience.
“His season was 9.9 out of 10,” Moya said at the Davis Cup.
After going through all that happened earlier in the year, winning two Grand Slams and ending as a world No. 1 is something unbelievable.
“In 2008 he was No 1, in 2019 he is so he totally evolved physically, mentally, game-wise, playing with new opponents. His ability to improve has been amazing.”
2019 VS 2010
Nadal has previously called 2010 his best year in the sport, and his achievements nine years ago are certainly impressive.
As in 2019, Nadal took home the French and US Open titles, but also won Wimbledon and four other calendar titles.
Rafael Nadal with the Wimbledon trophy in 2010
Image credit: PA Sport
But 2010 was a 24-year-old Nadal at the peak of his powers. That he is still dominating on the world stage almost a decade later after a number of injuries gives weight to the claim that while 2019 may not be as trophy-laden, the fact he has dominated an emerging generation of young players as well as the evergreen old guard of Roger Federer and Novak Djokovic may make it even more impressive.
NADAL'S PLACE AMONG TOP THREE
When it comes to Grand Slams, Nadal's haul of 19 sits between Federer's 20 and Djokovic's 16.
Few would doubt Nadal's chances of overhauling Federer's 20 given the Spaniard's dominance of the French Open, but it's that same monopolisation of one slam that can polarise critics who argue that Federer and Djokovic's more well-rounded slam domination gives them greater claims to being the best.
Nadal currently sits on 19 Grand Slam titles
Image credit: Eurosport
But another year like 2019 could put Nadal on a different level, while another Australian Open or Wimbledon title would do wonders for his already supreme legacy.
Whatever happens next, 2019 has been a remarkable year for a remarkable player at the top of his game with no signs of slowing. Expect more of the same in 2020.