Y.E. Yang, watch your back.
"I'm more looking at Y.E. Yang, now who's in second spot, trying to catch him," said Westwood, who goes into the third round 12 shots back. "Because if I'm going to win the tournament, then I'm going to need Rory to play poorly over the weekend."
Chances of that happening seem remote, considering the way McIlroy tore up Congressional Country Club in the first two rounds. But anything can happen in the U.S. Open on the weekend, and early leaders have a tendency to slip back toward the field.
Still, those bunched behind him don't seem to be holding out much hope.
"If he keeps playing the way he's playing it's going to be impossible to catch him," Brandt Snedeker said. "You're trying to shoot the lowest number you can. I personally won't look at the leaderboard all weekend because there's no point."
The players bunched well behind McIlroy include a few notable names along with a number of players few would recognize. What they have in common, though, is realizing the magnitude of the task facing them in the final two rounds of the Open.
Not since Tiger Woods was six shots clear of the field in the 2000 Open, has anyone led by this much in the modern history of the tournament. And players say that gap will have to close on Saturday for them to feel they have a chance.
"Right now it's completely and utterly irrelevant," 2007 Masters champion Zach Johnson said, referring to the scoreboard.
Just how far McIlroy was separating himself from the field was evident when he made double bogey on his final hole, something that usually brings a lot of players into contention. But his lead was so big all it did was make an impossible number look slightly less impossible.
"The way I look at it, the pressure is off me. I'm not the one that's supposed to win it right now," Johnson said. "I'm not saying I don't want to lead, but I don't know how many shots he's winning by. It's got to be at least seven, right? Eight, nine? You know, that's pretty good."
For the record, McIlroy's lead was 6 shots over Y.E. Yang, who knows a little something about coming back against big odds. Finding a way to beat McIlroy, though, might be even more difficult than overcoming a 2-shot deficit in the final round to beat Woods in the 2009 PGA Championship.
Yang had the misfortune of playing in the afternoon Friday, teeing off about the same time McIlroy finished and knowing what was ahead. He played well enough to be leading most Opens — adding a 69 to his opening 68 — but he's not even close in this one.
"I didn't even know his score when I teed off," Yang said. "So I just played my game. It actually enabled me to concentrate on my own game, so secretly I'm very happy that I had another under par round."
McIlroy's huge margin — fueled by two days of nearly flawless golf — seemed to take some spark out of the 37,000 spectators who jammed Congressional for what most expected would be a hard-fought Open. It also seemed to take some spark out of the afternoon wave of players, none of whom mounted any kind of a move toward the leader.
They were more fortunate than the morning players, who stared at the large scoreboard as they walked to the 18th green as if someone had mistakenly hung an 11-under number for McIlroy instead of 1-under. It was no mistake, though, as those playing in the group just in front of McIlroy already knew.
"I really wasn't worried about him," said Steve Stricker, who shot a 69 only to find himself 13 shots back. "The lead was too far away to be thinking about it."
If the rest of the players had any hope to take with them overnight it was that McIlroy has been in this position before and failed to finish it off. Most notable, of course, was the 4-shot lead he lost in the final round of the Masters, when he imploded on the 10th hole on his way to a fat 80.
But the record-setting rounds of 65 and 66 that McIlroy opened with at Congressional may have been more impressive than anything he did in the first three rounds on Augusta National.
"He's that kind of talent," Snedeker said. "Everybody knows it. It's great to see him do that, especially on the heels of the Masters."
For his part, McIlroy said he learned from his meltdown, particularly that he needs to be as aggressive in the final rounds as he is in the early rounds. Playing defensively was what got him into trouble in the final round at Augusta National, and he's determined not to do the same thing again.
"I know more than probably anyone else what can happen," McIlroy said. "So I've got to stay really focused and try and finish this thing off."
If he does, McIlroy will stake his claim as golf's best young player, something the sport desperately needs at a time when the future is uncertain for Woods. He will show the world what his fellow pros already know — that the 22-year-old from Northern Ireland is a rare kind of player who comes along only so often.
"I think everybody would agree he's probably got more talent in his pinky than I have in my whole body," Snedeker said. "I love watching him play because it's a very classical, beautiful golf swing. Once he matures and starts being out here for a while and being in these kind of situations, I think he's only going to get harder to beat. It's fun to kind of watch him grow up."