Every time Rafael Nadal walks out on court in a Grand Slam, you have that feeling of "Oh there could be an upset here, I hope not, but there could be one," owing to the woeful – by his own considerably high standards, of course – 2015 he has had.

In the first round of the US Open, the final Grand Slam of 2015, Nadal saw off the challenge of the talented teenager Borna Coric in four sets, and the Spaniard moved into the third round on Wednesday with a straight set win over Diego Schwartzman.

It wasn't as easy as one, two and three, though, for the former world number one, with Nadal losing his way a little in the first set, losing his serve when he looked primed for a 1-set-to-0 lead, but those fighting chops and big-match experience eventually proved to be enough in a 7-6 (7-5), 6-3, 7-5 victory.

Playing at the Louis Armstrong Stadium, rather than the one he usually is used to in the Arthur Ashe Stadium, Nadal was egged on by the vocal crowd, every time there was even the slightest sign of a potential loss in confidence.

"I feel that love," Nadal said. "I feel that energy. I always felt that energy when I'm playing in New York and a lot of places around the world.

"I think I was always nice with the crowd around the world trying to do as much autographs, as much photos with them.

"I think on the tennis court normally I have been doing the right things during my career, not breaking the racquet no one time in my career, not saying stupid thing on court, celebrating the point, saying bad things when I am not playing well.

"So the fans are happy with me. For me is the biggest satisfaction possible to feel the support of the crowd and the people, because that means a lot to me."

Nadal got a little tetchy when asked if he is aware of how "worried" the fans are over his form in 2015, where he even relinquished his seemingly unbreakable hold on the French Open.

"Seems like I am [world] No. 200 in every press conference," Nadal added. "I am not so bad. After I arrive here with the victory, I come back to the locker room saying how bad I am. Everyday.

"No, no, the fans, is normal that they are worried because I am worried, too. If I am not playing well, I am the first one who is worried.

"Seems like I come here, and seems like if I am saying the true, if I am being honest, it is bad. So then if I am being honest with you guys and I explain what happened to me, I explain if I am playing with nerves or with anxiousness like I did in Miami and I say after in the press conference, then I don't know what you want of me.

"In general, the people say, Why you say that? Why you are that honest? You give confidence to the opponent. I believe what happens outside the court, what we are talking about here isn't going to affect zero percent in the next result.

"The thing is you play well you have chances to win; you play bad, you are going to lose -- the sport is simple."

Nadal will want to continue on that simple path to victory when he plays the dangerous Fabio Fognini, a player he has had trouble against in the past, in the third round on Friday.