SPRINGFIELD, N.J. -- After Dustin Johnson signed for an opening 77 at Baltusrol Golf Club and marched right past waiting fans and media toward the parking lot, one might have expected the U.S. Open champion to bark at anyone who dared approach him.

Instead, as Johnson loaded his clubs into his courtesy Mercedes-Benz, he offered a bemused smile.

Such is the mindset of a guy playing the best golf of his career. Even your awful days don't seem so bad.

"I felt like I'm swinging well. It was just a bad day," Johnson said. "It's the first time I've played bad in a long time, so I'm not going to worry about it. Tomorrow's another day. I've just got to come out and shoot a good number."

The safe bet was Johnson would shoot a decent score in the first round of the PGA as well. His breakthrough at Oakmont was part of a run that included two wins and six consecutive top-10s. Fresh off a T-2 showing at last week's RBC Canadian Open and arriving at a golf course where his length would be a decided asset, Johnson was a popular pick to claim a second major of the season and supplant Jason Day as the No. 1 player in the world along the way. Instead, after two pars to start, Johnson double bogeyed the third hole, and never recovered.

Six over through 11 holes, Johnson figured he needed to make up some ground on one of the two closing par 5s. But he hooked his tee shot into the water on the par-5 18th, leading to another bogey. The 77 was his highest score since he shot the same number in the third round of the Players in May.

No one was more mystified than him, but one of the byproducts of such a heady summer is he knows he can turn things around in a hurry.

"It was just a rough day," he said. "Anything that could go wrong did. I had a good warm-up session, too. So it wasn't like. . . it just wasn't a good day. But it's not off by too much. I feel like I made some good swings, and they just ended up in bad spots."

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