Washington County Sheriff Dale Schmidt told the United States Golf Association he appeared to die of natural causes.
Thomas' dramatics happened on the 18 when he hit his second-shot three wood more than 300 yards on the par-five 667-yard finishing hole.
In July, Robert Streb became the 30th golfer to shoot 63 at the majors at the US PGA Championship.
Stricker, who played in the morning, wasn't 100 percent sure he would make the cut after his even-par 72 left him at 1-over for the tournament, though all signs pointed to him advancing to the weekend.More news: Watch the Golden State Warriors Championship Parade
It appears that Erin Hills, a first-time venue, has a lower threshold than the normal Open course. "It's still Saturday - 36 holes is a very long time in a U.S. Open". He lost the 2010 U.S. Junior Amateur final to Smithtown's Jim Liu, but he helped Alabama win the NCAA title in 2013 and the U.S. win the Walker Cup at National Golf Links of America in Southampton that same year. If I go out and shoot 65 or 85, I can still walk off the last green with one of my best mates in the world.
"He's upstairs and I'm down in the basement area", Fowler said.
Thomas shot a front nine score of 31, with six birdies and one bogey.
The putt ran past the hole and settled at the bottom of a collection area 70 feet away.
Day arrived at Erin Hills a week ago and felt "I put in the best preparation for any major in my career", he said. This is his third try at the U.S. Open and the first time he has made the cut. Unfortunately for him, a finishing bogey on the 18th, the easiest hole statistically in the championship, meant he is playing catch-up.
Brooke Henderson, the leader after each of the first two rounds, had a 67 to drop into a tie for second with Lee-Anne Pace (61), Sung Hyun Park (62) and Jenny Shin (63). This is only his second U.S. Open, finishing 27th in 2015.More news: My 2 Cents: Kevin Durant Wins Championship With The Warriors
Some of those who came out to the U.S. Open said they wanted to experience the tournament and check out the lovely Erin Hills Gold Course.
Another U.S. Open first for Xander Schauffele. Thomas rolled in an 18-footer that went right to left from the edge of the green.
Then again, none of the top 16 on the leaderboard has ever won a major.
Justin Thomas played two seasons for the Alabama men's golf team before turning professional in 2013. A run of 26 consecutive holes without a bogey ended when he rammed his long birdie putt on No. 9 about 12 feet by the hole and narrowly missed the par putt.
At the opposite end of the board it became a first in a Major with the current World No.1, No.2 and No.3 each missing the cut since the World Rankings began in April 1989.More news: LeBron James: Cleveland Cavaliers will continue building toward NBA Championship
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