Granted, Bubba Watson has the sleep habits of a 3-year-old.

“I need 12 hours of sleep or I get cranky,” he said Friday.

There are other traits that suggest he subscribes to the notion that it’s never too late to have a happy childhood.

And, yet, here is the flighty, self-taught, self-reliant, free-swinger from Bagdad, Fla. trying out another persona early at this U.S. Open.

Try to picture Bubba Watson as the adult in the room.

To all the irritations that might throw off the delicate, lace doily nature of the professional golfer — Oakmont’s glassy greens, its rough so thick you need a pardon from the governor to get released, the rains that turned the schedule to pulp — Watson so far has answered with a calm, positively grown-up acceptance.

Let others carp and moan about not being allowed a warm-up period after the first of three rain delays Thursday — oh, and they did, the poor souls.

Watson for one took that occasion to put together his best run of golf of the day. He came back from that break and birdied three consecutive holes. That was highlighted by a 49-foot putt on the 10th that travelled over hill and dale and took longer to fall than the Roman Empire.

“That hour delay gave me time to joke around with the boys and just have fun. I just got away from my own pressure that I’m putting on myself. It just freed me up, that delay,” he said.

Watson was 2 under through 14 holes when another storm finally washed out the rest of the first round. With a 7:30 a.m. appointment to finish the round the following day, Watson did the adult thing and turned off the TV that night without watching a moment of Cleveland-Golden State Game 6 so he could get that vital shut-eye.

He slept the sleep of the innocent. “I was in bed by 8:30. My alarm went off at 5:30.” In between, he knew nothing.

He returned to Oakmont, went 1 over for his last four holes and posted only the second under-par round of the 27 he has played over the course of 10 U.S. Open appearances.

Anywhere in red numbers is a very good place to be at Oakmont. Watson got to put his feet up on that 1 under and relax the rest of the day while the other half of the field played catch-up. He tweeted a message that he, his son Caleb and Jason Day’s young son Dash all went to a movie Friday afternoon. Meanwhile, Dash’s dad was getting his head kicked in by Oakmont.

It will be Watson’s turn to do play overtime Saturday, facing the prospect of trying to get in 36 holes.

With his explosive shot-making, Watson is known as the Masters specialist, winning that little spring fling twice. The other majors, not so much. The only time he has been better than T-18 at the U.S. Open was the last time it was at Oakmont (a T-5 in 2007).

The U.S. Open never has particularly suited Watson’s temperament. The USGA’s diabolical set-ups would not appear to match with the concept of Bubba Golf.

To see Watson bothered and out of sorts on occasion when things go sideways during a round makes the thought of him surviving the grim trials of an Open seem even less likely. The former Bulldog acknowledges that he’s prone to being like a Chihuahua on Red Bull when he’s playing. “I’m going to be jittery at The Travelers. I’m going to be jittery at Greenbriar. I’m not sure where else I’m playing — I’m going to be jittery at those places. It doesn’t matter (that) it’s a major.”

In Oakmont, at least, he feels he has some frame of reference, that he can be as comfortable here as at pretty much anyplace this side of Magnolia Lane.

“We’re always jumping around venues (at the majors, other than the Masters). So, I just know this course a little bit,” he said.

And he said he’s really embracing the attitude one must have to succeed at a U.S. Open. One of patience and forbearance, you know, those characteristics that haven’t exactly been a part of Bubba’s playbook.

“There’s many things that are going to cause a bogey. Maybe not you. Bogey happens. So you’ve got to be prepared for that,” he said Friday, as much for himself as for the media audience.

Sure, Watson could blow up when he starts his second round Saturday. The sheer volatility of his game is what makes it so very watchable.

But at least he will be rested for whatever the day will throw him.