2011 US Open: 3 Reasons Rory Mcllroy's Lead Isn't Safe

So here's the situation. Rory McIlroy has owned Congressional Country Club for two days. He just missed 36 holes of flawless golf, double-bogeying the 18th hole after his only poor tee shot of the day.

However, for more than one reason, McIlroy's six shot lead over Y.E. Yang, and nine stroke lead over the third place group is not safe. It's not that anyone wants to watch him collapse. Everyone wants to see him succeed. 

But there are a few reasons that McIlroy's lead may not be as safe as it seems.

Masters

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AUGUSTA, GA - APRIL 10: Rory McIlroy of Northern Ireland plays a shot back to the fairway on the tenth hole after an errant tee shot during the final round of the 2011 Masters Tournament at Augusta National Golf Club on April 10, 2011 in Augusta, Georgia

Let's get this out of the way.

McIlroy choked on the last day of a major. He shot 80. He collapsed under the pressure, and it is something that McIlroy will carry with him from now on.

Could this experience be one that's positive for Rory? Of course, but you have to wonder about him. McIlroy admitted he let his opportunity to set a record get in his head on Thursday. If he lets that in, will the Masters of 2011 creep back in?

Let's hope not. We've seen enough Dustin Johnson-like collapses in the past year and a half.

Conditions

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BETHESDA, MD - JUNE 17: Marcel Siem of Germany hits his third shot on the 18th hole during the second round of the 111th U.S. Open at Congressional Country Club on June 17, 2011 in Bethesda, Maryland. (Photo by Andrew Redington/Getty Images)

Get rid of Rory McIlroy this week, and Y.E. Yang has a three stroke lead. Get rid of Yang and you have a battle to the finish, probably with a playoff. 

But that doesn't mean there can't be a lead swing. If McIlroy takes his foot off the gas the next two days and shoots two or three over, and one person goes low, it's a tournament. 

The conditions are tough. Just look at the scores without Rory. That is how much better Rory McIlroy is when his game is on.

Y.E. Yang

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BETHESDA, MD - JUNE 17: Y.E. Yang of South Korea waves to fans on the 16th green during the second round of the 111th U.S. Open at Congressional Country Club on June 17, 2011 in Bethesda, Maryland. (Photo by Ross Kinnaird/Getty Images)

History lesson: 2009 PGA Championship at Hazeltine. Tiger Woods holds a six stroke advantage on one man after 36 holes. His name? Y.E. Yang. After 54 holes, it dwindled to three. And after that, Tiger's lead was no more.

Instead, Yang hoisted his bag, and then the trophy en route to his first major championship.

While most of the talk about Yang is overblown, he is still capable of winning. Especially if McIlroy does as Woods does, and comes back to the field. If there's one thing Y.E. Yang proved, it's that he is like Geoff Ogilvy—he knows where to stand when at a tournament when someone else chokes.