Compared with his past results in the tournament, it's night and day for the Australian former world No. 1.
Rory McIlroy shot his worst round ever at a U.S. Open, a 6-over 78, spending most of his day in the fescue.
Holywood's McIlroy finished four under for the final six holes, which helped the four-time major victor post a one-under-par 71 in Wisconsin, but the damage was done in the first round as McIlroy hit six over to effectively end his chances at the second major of the year.
For more sports coverage, visit the ABS-CBN Sports website. It looked as though the season's second major would be a continuation of recent weeks for the Canadian, in which his game feels good but the results aren't there.
At adjusted odds, Casey is the 8-1 second choice and Leishman is 18-1, along with Sergio Garcia and Justin Rose. So it's pretty simple, I just didn't get it in the hole fast enough.
"I'm assuming the USGA obviously doesn't like to see 7 under lead their championship at the start of the tournament", Day said, referring to Fowler's 65. The crew of six players at four under and five players at three under will have rolled through Erin Hills' (relatively) easy first two holes before the final pairings hit the course, and they could create a comeback.
On the golf course, there was only a barrage of birdies.
"Not your typical U.S. Open setup, but I'm a big fan", McIlroy said.
But Casey's momentum ran into the buffers on the next hole, when he twice found the thick rough and had to settle for a bogey five to drop back to six under.
"I just played bad golf, man", Day said.
Johnson was hitting it so well that he appeared to be safe even when he was on the cut line. Johnson capped off this collective failure with a late collapse on the back nine at Erin Hills, making three bogeys over a five-hole stretch and closing with a 73.
"I need to get competitive rounds, a card in my hand, " he said.
Jason Day of Australia, the world's No. 3-ranked player, experienced his share of difficulties, including a triple-bogey on the par-4, 451-yard fourth hole before finishing the day 7 over. The pristine Erin Hills will soak, and players will fall by the wayside because of it.
Day's meltdown began when not one, but two chips from the first cut of rough behind the fourth green hit the top of the hill, then trundled back down to nearly where Day was standing. It might sting a little more for McIlroy (+5) and Day (+10), who played in the same group and said after their round that they were consoling each other along the way.
"I had been swinging it well and it felt really, really good a couple holes later to be picking the ball out of the hole for a birdie".
"I was sticking to the same gameplan, I was doing the same things", said Hadwin, of Abbotsford, B.C.
"I think people - some of the guys took my social media post kind of the wrong way", Na said.
"It's going to be incredibly hard come the weekend, just because we've had the deluge (Wednesday) and the days leading into this".
"I'm playing next week in CT [in the Travelers Championship]".