Djokovic defeated Del Potro at the US Open to win his 14th title, putting him level with Pete Sampras, three behind Rafael Nadal and six adrift of Federer.
Djokovic is now tied with Sampras on number three in the list of players winning most number of grand slam titles in men's singles titles.
It's wonderful. I don't feel sad that I couldn't win grand slams because of them. He is now just three Slams behind Rafael Nadal and six back from the record 20 held by Roger Federer.
The 31-year-old Djokovic captured his second straight tennis major at the 2018 U.S. Open from Flushing Meadows-Corona Park in Queens, New York.
Djokovic had lost five previous finals at Flushing Meadows, but he was determined to make amends for his lack of trophies in NY as his defensive ability combined with his ruthless prowess saw him break in the fourth game, although Del Potro was not in the mood to give up so easily as he hit straight back. However, Djokovic had a slightly better percentage (15-for-19) and converted on his only break point opportunity to secure the set.
He had three more chances in the eighth, all saved by Djokovic in a marathon 20-minute game which left even Hollywood superstar Meryl Streep clasping her head in astonishment. After the third round, he did not lose a single set as he was able to outlast a fan favorite in Del Potro. He was barking at himself, at his entourage, at a crowd vocally supporting his opponent, Juan Martin del Potro. "I'm very sad for being a loser today but Novak deserved to take the trophy".
There appears to be one winning formula for Novak Djokovic when it comes to taking home the US Open title.
This was Djokovic's third championship in NY, along with those in 2011 and 2015.
The Serb walloped a forehand volley to safety on his first match point, dropping to the floor and spreading out on his back with his arms and legs outstretched in celebration.
Novak Djokovic won the U.S. Open on Sunday, his 14th Grand Slam championship. He played a great match, very smart game.
"I was playing at my limit nearly all the time, looking for winners", he said. "I know that he will be here again with the champions trophy".
The 13th-seeded team of Barty and Vandeweghe knocked of the No. 3 and No. 1 seeded teams en route to their first Grand Slam doubles title as a team.
While the scoreline suggested a comfortable evening for Djokovic, the Serbian was still made to work hard and had to produce some of his best and most consistent tennis. Del Potro would not rue how many of those could have been his had he been injury-free all those years.
Djokovic continued a remarkable summer after missing the end of last season with a right elbow injury.
It's del Potro's first major final since he won his only one in the 2009 U.S. Open by beating Roger Federer.