Rafael Nadal has ended up apologising to his defeated opponent Lorenzo Sonego after admonishing the Italian in a most uncharacteristic outburst during his one-sided third-round victory on Wimbledon's centre court.

The Spaniard, famed as the gentleman of the court who routinely treats his adversaries with utmost respect, lost his cool with the Italian in eyebrow-raising fashion during his 6-1 6-2 6-4 triumph on Saturday.

Nadal was left seething when Sonego tried successfully to get officials to close the roof so that the floodlights could be turned on in the late evening with the two-time champion on the verge of a straight-sets victory, leading 4-2 in the third set.

But with his victory charge having been halted, Nadal got even more annoyed on the resumption when the Italian roared his delight in the middle of a rally after pulling off a dazzling shot.

After then going on to drop serve for the first time in the match, Nadal beckoned Sonego to the net to lecture him about his behaviour.

Yet after calming down and racing to his victory, Nadal evidently recognised that perhaps he himself had been the one acting "unethically" for so publicly scolding the 27-year-old.

"First of all, I have to say that I was wrong. Probably I will not - I should not call him on the net," said the 36-year-old.

"So apologise for that. My mistake in that. No problem. I recognise that.

"Then after that, all the stuff during the match that I don't want to comment, because is something that I spoke with him in the locker room and it stays there.

"Only thing I can say is I saw him personally. I apologise for that.

"My intention was never to bother him at all. Just to tell one thing that was bothering me that I think he was doing in that moment, but that's it.

"I think there is some codes between players. Yeah, we had some issues there. But that's it."

It was hardly the sort of monumental bust-up that was occurring an overhit-serve away at the All England Club as Nick Kyrgios and Stefanos Tsitsipas got involved in one of the great Wimbledon ding-dongs.

But it was still most unusual for Nadal to feel impelled to tell the crowd afterwards: "From the bottom of my heart... I feel really bad now if I bothered him, so I feel sorry for that."

Nadal added later: "I think everyone have to go to the bed with being calm with the things that you have done, and if you can't sleep with calm and being satisfied with yourself, it's because you did thing that probably were not ethical, correct."

All this drama played out as Nadal played his "best match" at this year's Wimbledon, making the last 16 for the 10th time.

And he's making increasingly ominous progress towards annexing the third leg of a potential calendar grand slam .

The Australian Open and French Open champion, halfway towards emulating the great Rod Laver as the only man to win all four majors in a season in the Open era, quite outclassed the Italian 27th seed.

The 2008 and 2010 champion, seeking to extend his record to 23 grand slam triumphs, will be the warmest of favourites when he next tackles the Dutch No.21 seed Botic van de Zandschulp, who beat French veteran Richard Gasquet 7-5 2-6 7-6 (9-7) 6-1.