The two-time Wimbledon champion slumped to a 7-5 3-6 6-4 6-4 defeat by the German world No102 as Brown reached the third round of a Grand Slam for the first time.
The Spaniard has now lost in the second, first, fourth and second rounds on his past four visits to the All England Club – but the 29-year-old is remaining upbeat despite the disappointment of another early loss.
“At the end of the day, that’s sport – good moments, bad moments,” said Nadal. “Obviously today is a bad moment for me. I just need to accept these kind of things that can happen. I have done all my career. I will keep going.
“It’s not the end. Is a sad moment for me, as I said before, but life continues. My career, too. I have to keep going and working more than ever to try to change that dynamic.”
Nadal had only ever faced Brown once before, when the 30-year-old got the better of him at Halle last year.
He continued: [At Wimbledon in] 2012 and 2013, I told you before, I know I was not ready to compete well.
“This year I was ready to compete well, and I was playing well before the tournament. I had the right preparation – all the things I thought were going to be fine to play a good Wimbledon.
“I am not a person that will be thinking about it for the next two weeks. But obviously today it’s tough.”
Brown will next play Viktor Troicki, who beat Briton Aljaz Bedene.
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