Novak Djokovic admits his ultimate goal is to overhaul rivals Roger Federer and Rafael Nadal and hold the record for most grand slam titles.

Federer is currently out in front with 20 major men's singles titles to his name, but at 38 his chances of adding to that tally are dwindling.

Nadal, 33, is two behind the Swiss and Djokovic currently has 16 following his epic Wimbledon win over Federer last month.

The Serbian is favourite to defend his US Open title over the next fortnight to move onto Nadal's shoulders, and into Federer's rear-view mirror.

"It's still a very long way ahead of me," he said. "It does also put a certain level of responsibility to me as well, because I am aiming to do that.

"You know, it's definitely one of my ambitions and goals, if you want.

"I am 32. So things are a little bit different than they were 10 years ago, but I still feel young inside and outside. And I still am very motivated to keep going and especially at this stage.

"I mean, it's always been the case but, especially now, more or less everything is about grand slams in terms of how I see tennis and how I approach them because, you know, they matter the most.

"So I will definitely try to play my best tennis and aim to play my best tennis at this event."

Djokovic admitted his Wimbledon win, after a historic tie-break at 12-12 in the deciding set, was one of his most memorable matches.

"It's in the top two matches I have ever played," he added. "The other match is the one against Nadal in the final of the (2012) Australian Open which went almost for six hours.

"So those two matches really are very special and take a special place in my career and my mind as well.

"I still have flashes from the Australian match, many years after. And of course I would wish to remember the Wimbledon final against Roger this year for many years to come."

Former Wimbledon runner-up Kevin Anderson has withdrawn from the US Open with a knee injury.