Rafael Nadal believes the three major wins he needs to match Roger Federer's record haul of 19 men's singles titles in the Open Era represents a "big difference".
Nadal won the 16th grand slam of his career when he beat Kevin Anderson 6-3 6-3 6-4 in the US Open final at Flushing Meadows on Sunday.
It represented the world number one's second major win of the year, the other being his historic 10th French Open victory, in a dramatic change of fortunes from an injury-ravaged 2016.
Nadal was beaten in the final of the Australian Open by Federer, the 36-year-old Swiss also winning his eighth Wimbledon title in a phenomenal return from knee and back issues the previous year.
Asked about matching long-time rival Federer's tally, Nadal said: "I really never thought much about that. I just do my way. He does his way. Let's see when we finish.
"Of course, if I won two grand slams this year and he did not win, we'd be closer, but he has 19, I have 16. So three is a big difference.
"I'm very happy with all the things that are happening to me, winning this title again. I have this trophy with me.
"It's so important, winning on hard court again. That's a lot of positive energy for me. Being healthy, you see everything more possible. With injuries, everything seems impossible.
"It's true that I am 31, I am not 25, but I still have the passion and the love for the game. I still want to compete and still feel the nerves every time that I go on court. While those things keep happening, I will be here."