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McIlroy arrived at Erin Hills last Friday.
Knox, one of three Scots in the field - alongside Martin Laird and Richie Ramsay - is unfazed by controversy over the heavy rough on the course. American professional Kevin Na caused a stir this week with an Instagram post in which he pilloried the length of the rough at Erin Hills, but it did not ring true with Day, nor with Rory McIlroy, who said the deeper rough was so wide that it should not be an issue other than for a bad shot. It will allow guys to be aggressive, you'll hit a lot of drivers around here and you can be aggressive with your iron shots.
"I think past year there were two things we fell short on - it took too long to make the ruling and it left uncertainty with the competition", said John Bodenhamer, the USGA's managing director of rules and competition.
Knox, who is 39th in the world rankings, is content with his game after finishing tied for 37th at the FedEx St. Jude Classic in Memphis.
"Obviously I've had a few weeks off to try and rest this injury that I've had all year, but I feel good", he added.
"For those players who are making a big deal about the high, thick fescue along the 7,800-yard setup at Erin Hills, host of the U.S. Open this week, saying it's" unplayable", "unhittable", "unfindable", and that it's, yes, all so "unbelievable", I say, "quit whining!" "They both are. But I think they'll play tremendously different".
"I teed off a little too on the defensive side, tried to respect the golf course too much and not playing as aggressive as I did", Rahm said. It's hard, there are a couple of good, hard holes.
"So moving forward we want a nice, smooth US Open". It's not supposed to be easy. You're just putting more effort into each round. And actually, I absolutely love the golf course.
"It would mean the world (to play)".
"If you're in that stuff, then honestly, you might lose your ball".
The 32-year-old had seen his ball move fractionally as he lined up a putt, but called in the referee walking with his group and was initially cleared of any wrongdoing before holing out for par. If I pick one (a win) up here, great. And I feel like it's the same thing here.
There are 17 other players from the 2011 Amateur who are in the field for the 2017 U.S. Open. "And downwind, if the greens are firm, which it doesn't look like they're going to be, but if it was firm, it leaves an nearly impossible shot if you're outside 120 yards just to hold the green". If I swing it like I have been the last week or so, which there's no reason why I shouldn't, I think I'll have a good week. "I wasn't sure I was going to be here, but very excited ... relieved".More news: Microsoft Announces 'Minecraft: Better Together' Update: Cross-Play On Any Device