Nadal is scheduled to play fellow Spaniard David Ferrer in the third round of the Barcelona Open this afternoon.
The eleven-time Barcelona Open handed the first set to Leonardo Mayer in its second round on Wednesday, but managed to get through in three sets.
However, after the game, Nadal was far from happy with how he competed.
"It wasn't the best start, not the best feelings out there this afternoon, but I found a way to keep going and win the race," said Nadal.
"[Mayer] competes well with everyone, but probably today [the problem] wasn't that he competed very well against me.
"I didn't compete so well."
Nadal didn't seem to be struggling with an injury to Mayer, but in practice this morning, the 32-year-old was in visible discomfort in footage captured by television broadcaster RTVE.
The clip shows that Nadal hits two consecutive forehels before shaking his head after lowering a third shot.
Nadal then shook his hand a few times and walked over to his physio Rafael Maymo, who massaged his wrist.
After a short time that his wrist was working, Nadal walked back to the baseline and kept on bouncing.
Nadal experienced hand problems when participating in the Acapulco Open in February.
But the pain of Nadal will give him and his fans new worries after a difficult year with injuries.
Since November last year, Nadal has been struggling with problems related to the abdomen, ankle, thigh, knee and hand, and he talked about the tension that the injuries have in his way of thinking.
He said, "The problem is that sometimes we are very, very solid and even come back from injuries, winning and winning and winning, and things are not easy, are we?
"And after a year and a half, without having the chance to play tournaments in a row and many things have happened, it is sometimes harder to maintain the level every day if you do not trust tournaments in a row, no, or competitions in a row.
"And that's what I probably needed to know that half the level, I got it. Even if I've been very competitive in all the tournaments I've played, all these stops create some instability in terms of knowing you you have 60 or 70 percent of your level, 100 percent.
"Then some days you have those 90 or 100, but these 70, you always have it.
"That is why I have been able to win all the things I have won, especially clay. And today it seems like I did it the previous days, but it is always more difficult if all these things are going on."