Former world number one Djokovic equalled Pete Sampras' haul of 14 slams after outlasting Del Potro 6-3 7-6 (7-4) 6-3 to lift the trophy for a third time in NY.
"He respects everyone", Djokovic said.
It was Djokovic´s 15th win over the Argentine and his fifth in five at the Slams.
Before Friday, Djokovic seemed likely to face Rafael Nadal in the final until Nadal was forced to retire due to injury after his second set against del Potro.
Del Potro - the 2009 champion back for a second slam final after overcoming career-threatening wrist injuries - threw everything he had at his rival, but Djokovic absorbed the Argentinian's power superbly, his returning of serve particularly outstanding.
"I don't feel sad that I couldn't win Grand Slams because of them".
"We have pushed each other to the limit every time we get to play each other".
It was a magnificent night of tennis from both players, where Djokovic's athleticism, court coverage and tennis brains came out triumphant against Del Potro's big serve and forehand.
AS with any final weekend of a grand slam there was plenty of cash being dished out at the US Open the past couple of days.
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Zidane has worked with both Kroos and Rodriguez during his time at Real Madrid , and is a big fan of Thiago's work in midfield. During that time he won nine titles with the club, including the three successive European Cups.
There was a moment in the match when Del Potro's singing friends managed to distract Djokovic and make him lose his focus but he fought on like a champion and emerged the victor under the closed roof of Arthur Ashe Stadium.
Novak Djokovic of Serbia poses with the championship trophy after winning his men's Singles finals match as Juan Martin del Potro of Argentina looks on on Day Fourteen of the 2018 US Open at the USTA Billie Jean King National Tennis Center on Sun., Sept. 9, 2018, in the Flushing neighborhood of the Queens borough of New York City. But when Djokovic faced three break points in the following game, an epic that required 22 points to settle, he saved them all.
He picked up the pace with straight-sets victories over France's Richard Gasquet, Portugal's Joao Sousa, Millman and 2014 finalist Kei Nishikori to arrive at a title tilt with good friend Del Potro.
Djokovic glared at the crowd and tossed his hands up in disbelief after losing one 16-shot rally, then he steadied himself and fended off three game points that would have given del Potro a two-game lead in the set.
He closed his win with a yelp, barely audible over del Potro's ebullient fans.
"If you told me in February this year when I got the surgery that I'll win Wimbledon, U.S. Open, and Cincinnati, would be hard to believe", said Djokovic, after pushing his career total to 14 Grand Slams to sit equal third with Pete Sampras on the all-time list. "I think that's why people love him". Nadal is the first man to retire from a semifinal or final at the US Open since the professional era began in 1968.
Djokovic then won the tie-break from 1-3 down to clinch a 95-minute set and, although Del Potro also threatened a comeback in the third, there was no doubt who was the stronger player. "I'm glad I managed to do that".
"You can learn a lot from the past but I want to focus my energy on the present".