No greater proof of that came than tonight as the defending Women’s Champion and current No. 2 seed fought off bad play and tough conditions to beat No. 6 seed Sam Stosur, 6-4 5-7 6-3, in their Quarterfinal matchup to improve to 19-0 over the past two years.

And how did Mrs. Lynch win it?

“I think by mentally just staying focused out there,” she said.  “You know, I felt that I was really reading her serve well in the return games.  I really felt that I was just ‑‑ even, you know, those heavy kick serves I felt I was getting into her backhand well, and, yeah, just made her go for some errors.

“Obviously she, you know, wasn’t serving great, either.  I just really felt that, you know, if I could just get that return deep, I felt that I was, you know, kind of in charge of a lot of rallies.”

It got so bad that Clijsters and Stocur could not hold serve on the first seven games of the third set. Part of it reason was the wind, as both players could not have that hard first serve land where they wanted it.

And part was because both players didn’t have their strong games out there, as both admitted after the match.

“Yeah, it was definitely tough conditions, windiest conditions I’ve played in all week, and probably the worst I’ve served all week, as well,” said Stocur, who had her highest finish at the Open of her career.  “Put those two things together, and you don’t hold serve for the third set and you lose.”

“I still didn’t play a good match, but I was obviously able to win it,” Clijsters said.  “That’s obviously, at the end of the day, what we try to do out here, is try to win the matches whether you play good or bad.

“Like I said, even after the match, I was like, How did I win this?  I didn’t feel like I was playing well.  Sam is a good player, you know, so I was just kind of ‑‑ yeah, talking to my coach and fitness coach and just, Wow, what just happened?  How did I win?”

Well it was just sheer guts and guile on Clijsters behalf. She was able to utilize her speed and eventually held serve in Game 8 of the third set. When that happened, it was all over. In fact, she then broke the Australian in the final game with the winner coming on an ace.

“Yeah, that’s probably all the frustration that comes out at the end,” Clijsters said.  “I’m like, I don’t like to hit one more rally.  I just want to finish it with a good shot.  Um, I don’t know.  It’s the rhythm.  It’s been frustrating.”

Clijsters now faces Venus Williams in the Semifinals on Friday. This will be a rubber match of their career head-to-head with both players winning six apiece. But Clijsters has won the last four matches, including the Round of 16 at last year’s US Open, 6-0 0-6 6-4.

But Mrs. Lynch is not taking anything for granted.

“I think obviously the way that she’s been playing and the way that she has mentally looked,” Clijsters said. “I think it’s maybe been even been good for her to have been away for that long, because she looks more hungry than ever.”

FLUSHING MEADOWS, NY – New York City may own Flushing Meadows-Corona Park and the deed to Arthur Ashe Stadium is in the name of the USTA, but for the last two years, Kim Clijsters owns the US Open.

No greater proof of that came than tonight as the defending Women’s Champion and current No. 2 seed fought off bad play and tough conditions to beat No. 6 seed Sam Stosur, 6-4 5-7 6-3, in their Quarterfinal matchup to improve to 19-0 over the past two years.

And how did Mrs. Lynch win it?

“I think by mentally just staying focused out there,” she said.  “You know, I felt that I was really reading her serve well in the return games.  I really felt that I was just ‑‑ even, you know, those heavy kick serves I felt I was getting into her backhand well, and, yeah, just made her go for some errors.

“Obviously she, you know, wasn’t serving great, either.  I just really felt that, you know, if I could just get that return deep, I felt that I was, you know, kind of in charge of a lot of rallies.”

It got so bad that Clijsters and Stocur could not hold serve on the first seven games of the third set. Part of it reason was the wind, as both players could not have that hard first serve land where they wanted it.

And part was because both players didn’t have their strong games out there, as both admitted after the match.

“Yeah, it was definitely tough conditions, windiest conditions I’ve played in all week, and probably the worst I’ve served all week, as well,” said Stocur, who had her highest finish at the Open of her career.  “Put those two things together, and you don’t hold serve for the third set and you lose.”

“I still didn’t play a good match, but I was obviously able to win it,” Clijsters said.  “That’s obviously, at the end of the day, what we try to do out here, is try to win the matches whether you play good or bad.

“Like I said, even after the match, I was like, How did I win this?  I didn’t feel like I was playing well.  Sam is a good player, you know, so I was just kind of ‑‑ yeah, talking to my coach and fitness coach and just, Wow, what just happened?  How did I win?”

Well it was just sheer guts and guile on Clijsters behalf. She was able to utilize her speed and eventually held serve in Game 8 of the third set. When that happened, it was all over. In fact, she then broke the Australian in the final game with the winner coming on an ace.

“Yeah, that’s probably all the frustration that comes out at the end,” Clijsters said.  “I’m like, I don’t like to hit one more rally.  I just want to finish it with a good shot.  Um, I don’t know.  It’s the rhythm.  It’s been frustrating.”

Clijsters now faces Venus Williams in the Semifinals on Friday. This will be a rubber match of their career head-to-head with both players winning six apiece. But Clijsters has won the last four matches, including the Round of 16 at last year’s US Open, 6-0 0-6 6-4.

But Mrs. Lynch is not taking anything for granted.

“I think obviously the way that she’s been playing and the way that she has mentally looked,” Clijsters said. “I think it’s maybe been even been good for her to have been away for that long, because she looks more hungry than ever.”

“I’m sorry,” del Potro told a chuckling crowd which he earlier thanked for their support at his favorite event while speaking with ESPN’s Darren Cahill. “But tomorrow, I’ll fight until the final point for you, for everyone, to show good tennis.”

“It’s part of my dream, you know. I’m very close to do it, but this moment is so nice, and I always dreamed of this moment.

I’m very happy to beat Rafa in straight sets, play unbelievable match. Of course it’s great for me and for my future being in finals.”

The 20 year-old Del Potro had other ideas playing remarkable tennis to dominate one of the game’s best, crushing Rafael Nadal in the first men’s semifinal 6-2, 6-2, 6-2 before a stunned Ashe Stadium in Flushing this afternoon.

Maybe the wear and tear finally caught up to the six-time grand slam winner who was playing a day after dismantling Fernando Gonzalez with a heavily wrapped stomach due to an abdominal strain he’d nursed throughout the final slam of the season. Even if the gutsy 23 year-old Spaniard wasn’t at his peak, a lot of that had to do with his opponent who played a perfect match to make his first ever slam final where he’ll await the winner between Roger Federer and Novak Djokovic taking place later.

“I think this is the best moment of my life,” the excited del Potro said after becoming the first Argentine to reach the men’s final since Guillermo Vilas in 1977 to a nice reception.

“Just have to congratulate him,” said Nadal who had nothing to be ashamed of.

In his first Open semi, a locked in Del Potro just had too much in his arsenal turning the match into a rout. The six games he permitted was the worst beating Nadal had ever taken in a slam match with only Frenchman Jo-Wilfried Tsonga faring worse when he dropped seven games in a 2008 Australian Open semifinal.

Unlike his come from behind four set quarter win over Marin Cilic, Del Potro came out sharp firing on all cylinders. Early on, both players had some scintillating rallies making the first few games very long. That included a fun point that had Nadal scrambling even pulling a crowd pleasing tweener which Del Potro volleyed back that a stumbling Rafa couldn’t finish off.

Nadal had his chances including an early opportunity to break but with his bread and butter forehand setup, he missed just wide blowing it which allowed Del Potro to crawl out of the third game. That would be a common theme with the younger Argentinian serving out of trouble by fighting off all five break chances while he remained aggressive, converting six of 16 on Nadal’s serve.

The first break came in the next game. After Nadal couldn’t put it away, a hustling Del Potro forced a backhand volley long that gave him an early 3-1 lead. A frustrated Rafa tapped his leg perhaps realizing how crucial that moment was.

Nadal tried to come back but Del Potro served well all day with the sun peering out following the dreary weather that caused so many scheduling gliches. When he needed a big serve, the lanky 6-6 fifth year pro took advantage of his big frame to find the angles forcing errant replies. He only had six aces but it felt like more due to the velocity and placement which gave Nadal trouble. For the match, Del Potro won 79 percent on his first serve (44 of 56) compared to 57 percent (40 of 70) for his more accomplished foe.

“I played a great match. I was so focused with my serve, with every breakpoints, playing serve, you know, trying to put the ball into the court and trying to be aggressive,” explained del Potro of why it went so well.

Still down a break at 2-5, Nadal tried to hold serve and stay in the set but ultimately, he was outhit by Del Potro who mixed in a lethal backhand which drew miscues off the normally solid Rafa forehand. The firepower he came with was too much closing the set with a forehand winner.

Undeterred, Nadal continued to throw everything at Del Potro and had a slight opening in the first game of the second set. But once again, the sixth seed used his serve to get out of trouble with a couple of service winners flustering Nadal. The combination of his bigger serve along with penetrating groundstrokes gave him a decided edge finishing with 14 more winners (33-19).

If not for Rafa’s speed and competitiveness, it could’ve been a lot more. Instead, Del Potro who stepped inside the baseline to control rallies earned more unforced errors off Nadal’s racket. A rarity. He committed 27 to Del Potro’s 28. Not bad but given how big the player who beat him in Montreal last month was hitting, it was easy to see why the French Open semifinalist had entered winning 16 of his last 17 since Wimbledon.

It didn’t take long for Del Potro to break earning another on a double fault for a 3-1 lead. With the crowd trying to rally the struggling Nadal, Rafa continued to put in a maximum effort running down every ball. However, Del Potro just wouldn’t miss.

Even when there was a slight opening, it was closed quickly. Up 5-2, Del Potro didn’t slow down breaking Nadal a fourth time to go up two sets. Despite only dropping four games at that point, he still needed an average of 50.5 minutes to win the sets giving an indication of how hard Rafa tried even when it wasn’t his day.

“The first two sets was 6 2, but I have a lot of chances, I think. A lot of chance to keep the score more tight. If it’s like this, you never know what happened. But nothing to do today,” Nadal pointed out.

By the third set, the outcome looked certain. Nadal continued to compete but a streaking Del Potro didn’t take his foot off the gas pedal accelerating with more tremendous hitting that featured some wicked winners including an inside out forehand and a backhand cross that was Agassi-like.

So dominant was he from the ground that he pinned Nadal behind the baseline even finishing off points at the net where he did well converting 71 percent (17 of 24).

“I saw Rafa in the baseline, but too far away on the baseline. That’s important for me to come to the net and to do a short point.”

Del Potro also punished Rafa’s second serve taking 14 of 20 points. While he struggled himself in that department dropping 17 of 29, they weren’t frequent enough and never came at critical moments.

Already leading by a break 5-2, he went for the kill easily breaking Nadal a sixth time when the 2009 Australian Open champion sent a forehand way long for the biggest win of his career.

An overjoyed Del Potro pumped his fists in almost disbelief before receiving congrats from a wounded Nadal, who made no excuses in a brief postmatch interview with ESPN’s Pam Shriver.

“Here, it was disappointing, I had a little bit of a (bad) break,” Nadal said while giving Del Potro his due. “The right abdominal. To compete with these players was difficult.”

“I did a good result, very positive result for me after coming back. Semifinals. Today he played better than me. He beat me, and right now I just try to recover. Is not very important injury, so that’s really important for me, too.”

Most players after such a defeat would’ve dodged the questions and walked off the court. But not Nadal who even was nice enough to sign autographs for fans winning even more.

A night before, we saw the worst in a player who lost her mind handling a tough situation very poorly typifying what’s wrong with today’s athletes. Today, even in defeat, we saw what’s very right and why Rafa Nadal is so easy to respect and root for.

It just wasn’t his day. Today was about a rising star who should move up to No.5 in the world no matter what happens in tomorrow’s Monday final to be seen on CBS at 1 PM.

“I think so,” del Potro assessed on if it was his best win. “It was so focused every moment because Rafa’s a great player. He can run for 5, 6 hours. I’m not very strong but I do my best, and I’m in the final.”

“I don’t remember, but I think was I saw the stadium too big, and I say, This will be my favorite tournament.”

Now he’s one match away from winning it.

“I hope to be quiet for tomorrow to enjoy the moment, but could be difficult for me, because I never play a Grand Slam final.

“But I have the game to win tomorrow. I just want to be focused with my tennis and try to beat Roger or Novak.”