With three par-5s you need to score on them, fortunately I birdied the 15th when I got to 12 feet with my first two shots and the eagle putt hung onto the lip but it was still a birdie.
Hideki Matsuyama rode a roller-coaster as he opened with two birdies, but turned in one-under.
Top scores (USA unless specified): 67: Thorbjorn Olesen (Den), Kevin Kisner.
Kisner is not ranked 25th in the world for nothing, even if his name does not carry a lot of cache.
But lots of hard work with his coach, John Tillery, grooved his swing and restored his confidence. "I feel like I have the game to compete in majors, and tons of 30th- to 40th-, 50th-place finishes".
Thomas, who led Alabama to the 2013 championship, carded a 2-over 73 after hitting only seven of 14 fairways in what he called a "real struggle" of a round.
"I was hitting the ball OK but my scrambling was woeful", he said.
Fowler could have threatened for the lead had it not been for an ugly triple bogey at the par-4 fifth.
"This golf course, it's a bomber's paradise I think", said the muscular Koepka. You don't want to be playing out of the rough.
"I've always played other sports throughout my life, and I've never been the biggest guy, so I had to find a way to get things done", he said.More news: Antero Resources Corporation (AR)
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Given the size of Quail Hollow, Kisner drew up a simple plan: He identified four or five holes where he could make birdie and he played for par everywhere else.
In the first round, Spieth nearly lost a chance to connect when he birdied two consecutive holes before putting two birdies to get back into the chase for another Grand Slam. "I got my arse kicked a little bit yesterday on my back nine".
"Obviously Kisner is on fire". "I haven't hit it this well this whole summer".
Jordan Spieth, after an opening 72, had a late tee time on Friday.
Spieth was happy to get through with a 72 in his quest to become the sixth player to complete the career Grand Slam.
Among them is junior golfer Elizabeth Ritchie, who transferred over the summer to Havelock High School.
Getting "put on the clock" involves officials approaching a playing group who are playing slowly in order to keep up the rate of play with groups behind them.
Added four-time major champion Rory McIlroy, who also shot 72, "The greens were hard".
"I'm probably not playing as well as I did at the end of previous year", Matsuyama said.