Gracious losers, and winners, are, sadly, rare in professional sports. Rafael Nadal’s performance Monday night, after losing this year’s United States Open, was the very essence of graciousness and a reminder of what good sportsmanship really means.

On court, Mr. Nadal plays a relentless, slashing game. Off court, he is nearly always polite and soft-spoken. He had to be deeply tired and frustrated after losing the championship to Novak Djokovic in four grueling sets — his sixth straight loss to his rival. But at the postmatch press conference, Mr. Nadal refused to make excuses or look to blame anyone but himself.

When reporters opened by asking about a medical timeout Mr. Djokovic had taken, Mr. Nadal said, “We are starting the press conference in a bad way, I think. It’s not the right moment to find excuses.” When he was asked whether Mr. Djokovic’s evident back pain gave Mr. Nadal hope during the match, he said, simply, “My hope is always about myself, not about the opponent.” As for any future Nadal-Djokovic matches, he said, “It’s going to be tough to change the situation, but the goal is easy to see.”

It was moving to watch a man who had played with so much heart also speak with so much heart. His praise for Mr. Djokovic, who is having one of the greatest seasons ever, was generous and accurate. But the thing of beauty — and the very ethic behind his game — was the self-recognition in Mr. Nadal’s words, the sense of his personal responsibility for what happens to him on the court. It can be summed up in one of his own phrases, uttered with a terse eloquence: “Accept the challenge, and work.”