Another estimable opponent of the highest ranking, another major-tournament championship test, another dare to put his chronically troublesome knees through two weeks of hard-court punishment merely served as accelerant for Rafael Nadal.
The man is on fire. With his 6-2, 3-6, 6-4, 6-1 victory over top-seeded Novak Djokovic in Monday night's U.S. Open championship match, Nadal won his second Grand Slam event and 10th of 13 tournaments entered this year. He ran his 2013 match won-lost record to 60-3, 22-0 on hard courts, once considered his least kindly surface.
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"This is probably the most emotional one in my career," Nadal said. "I felt like I did everything right to have my chance here. You play one match against one of the best players, No. 1 in the world, so I know I have to be almost perfect to win."
In claiming his latest Big Door Prize of tennis, Nadal had to trade punches with Djokovic -- winner of this year's Australian Open and champion in five of the previous 11 majors -- for more than three hours. A single point late in the second set required a dizzying, exhausting 54 shots.
Djokovic hit 46 winners to Nadal's 27. Nadal won the trade-off on unforced errors, making only 20 compared with Djokovic's 53, though it could be argued that many of the unforced errors by both men felt forced by the other's persistence in their countless rallies of attrition.
It was not until late in the fourth set that Djokovic began to crack, and only after Nadal barely extricated himself from a possible two-sets-to-one deficit. After splitting the first two sets, Nadal was facing a triple break point at 4-4, 0-40.
"Novak was playing amazing," Nadal said, "and when Novak plays that level, I'm not sure if anybody can stop him. I know that it was really important to stay only one break behind."
He hit a forehand winner, outlasted Djokovic in a 21-stroke point, cracked a 125 mile-per-hour ace -- his first and only one of the match -- and chased Djokovic into the corner to set up an overhead winner for a 5-4 lead.
"Disappointing," Djokovic said. "I felt like, in the first four, five games of the set, I was the one dictating the play. He started playing really good. I didn't do anything wrong on those few points, but he didn't make a mistake. Next thing you know, all of a sudden, it's two sets to one for him."
Then, having hijacked Djokovic's golden opportunity, Nadal immediately produced his own service break to close out the set. And burned Djokovic again in the second game of the fourth set with another service break.
Only minutes later, Nadal was rolling on the court in a combination of celebration and relief.
It was the 37th career duel between the best that Spain and Serbia has to offer the sport -- a men's record since the dawning of open tennis in 1968. The two played for 4 hours, 37 minutes before Nadal prevailed in this year's French Open semifinal and for 5:53 before Djokovic won the 2012 Australian Open final.
Nadal called their confrontations "special, and when you have the chance to win against the most difficult players, it's true that the victory is more special. Most important is to win the tournament, not the opponent."
By claiming his 13th career major-tournament title, Nadal trails only Roger Federer (17) and Pete Sampras (14) in Grand Slam trophies -- even as he seems to be getting better.
"Thirteen Grand Slams for a guy who is 27 years old is incredible," said Djokovic, himself 26 with six major championships. A conflagration of excellence.