My, my, my, Marin Cilic has taken out Andy Murray in the round of 16 at the U.S. Open and it wasn’t close. On the flip side, Kim Clijsters beat Li Na in the quarterfinals and that wasn’t close either. What do I mean by flip side? Murray had tons of expectations and Clijsters very few.

Clijsters was famous for being “the best player never to have won a slam” before winning the 2005 U.S. Open then retiring in the spring of 2007. And now she’s managed to do something that is very rare: create a low pressure situation for a seasoned professional. She did it by leaving the tour for two years then returning with a kid in tow. When I twitted this theory, ESPN’s Bonnie D. Ford responded by pointing out that Clijsters did choose to come back in the heart of the U.S. Open Series. True, but all the more reason for expectations to be lower.

Murray may have an excuse. He might have a wrist injury. We won’t really know until he comes out with his second (and counting) memoir in which he might reveal that his wrist was killing him by way of explaining how it took him so long to win his first slam. Anything but the pressure. For example, look at this exchange after he lost to Cilic:

Q. There were some people that were picking you to win this tournament coming in. Did you ever feel any pressure or expectations on you?
ANDY MURRAY: No. I put pressure on myself to win the tournaments. I mean, it’s nice to hear sometimes from the other players or, you know, ex players, but it doesn’t really make a difference to who win who wins or loses the tournament. They’re not out there on the court with you, so it doesn’t make any difference.

No genuine pretender to the crown admits to injury or weakness under pressure and that may be part of Dinara Safina’s problem. I can’t remember the last time any player was under such pressure to win a slam and while it’s not nice to blame the victim, she does feed the frenzy by repeatedly discussing her mental weaknesses as she did again this weak:

I go to the court with so much that I want to win, and I put so much tension in it, I guess, not to lose, and that’s why I’m not playing relaxed, instead of just going out there and just play, let it go. I can’t control when I lose but, come on, do your thing. But I’m in too much not to lose a match. It’s blocking me.

Safina’s main source of pressure, Serena Williams, has little pressure herself. She has now won three of the last four slams and absolutely nothing in between. She’s the anti-Dinara. By the way, has anyone ever done that before? Pete Sampras didn’t win anything in the two years between his 2000 Wimbledon title and his 2002 U.S. Open title. That’s the best I’ve got. Anyone got anything else?

In the parallel realm of U.S. Open pressure, here are few ratings. Feel free to add your own:

1. Roger Federer: Hasn’t had this little pressure since he was hitting gorgeous backhands as a 12-year-old at Old Boys Tennis Club in Basel. He’s already passed Pete Sampra with 15 slams, he’s got the career slam, and he has the built in excuse of tiny twins to distract his attention and keep him up all night.
2. Juan Martin Del Potro: He’s only 20 years old, he didn’t really emerge until last year, he’s still growing into his body… Medium pressure.
3. Melanie Oudin: She beat Elena Dementieva and Maria Sharapova to reach the quarterfinals. Anything past the first round is unexpected for her. Negative pressure, meaning less than zero.
4. Rafael Nadal: It’s a curious thing now that I think about it but I seldom think of pressure affecting Nadal. His attitude is so humble and his media responses are so measured that we know very little about what goes on in his mind. I’m inclined to believe what he said after beating Gael Monfils today and taking back the number two ranking from Murray: “I say it every day. I am here just to try my best.” Boring but true and, incidentally, probably the healthiest attitude out there.

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