Bill Haas claimed the clubhouse lead in the 78th US Masters as the shortest hole at Augusta National had a major impact on two players attempting to enter the record books.
Haas, whose father Jay was third here in 1995, carded an opening 68 to finish four under par, one shot ahead of defending champion Adam Scott, with Masters rookies Kevin Stadler, Jonas Blixt and Jimmy Walker among a six-strong group on two under.
Scott had been four under par after a flawless opening 11 holes, with one of his birdies coming on the par-four 10th where he sealed victory on the second hole of a play-off with Angel Cabrera last year.
But the Australian - aiming to join Jack Nicklaus, Nick Faldo and Tiger Woods in winning back-to-back titles - then dumped his tee shot on the 12th into Rae's Creek in front of the green to run up a double-bogey five, before three-putting from long range for par on the 13th and 15th.
"I was very happy with the way I played today tee to green," said Scott, whose 69 matched his lowest opening round at the Masters from last year and 2010. "It was really how you hope to come out and play at any major, and especially the Masters. I was really solid.
"I hit the one poor shot on 12, which obviously cost me a couple of shots, but very pleased to get off to a good start and there's no doubt winning the Masters last year had me a little more comfortable on the first tee than I've ever been in the past, because I didn't have the legs shaking and nerves jangling for six or seven holes like usual, so that was enjoyable for me today."
Three groups ahead of Scott, 50-year-old Miguel Angel Jimenez was also four under after 10 holes in his bid to become the oldest winner of any major championship, Julius Boros being 48 years, four months and 18 days when he won the US PGA Championship in 1968.
However, the Spaniard then dropped a shot on the 11th and also found water off the tee on the 155-yard 12th to card a double bogey on his way to a 71.
Pre-tournament favourite Rory McIlroy safely found the 12th green in regulation but three-putted for a bogey and did the same on the 18th to also card a 71.
"It was a good day at the office, anything in red figures was a good effort out there," McIlroy said. "When I saw the pin positions this morning I thought they didn't want people to get too many under par.
"They've got the greens very fast already, by Sunday they are going to be pretty dicey. Going out tomorrow afternoon I would not mind if they were a little gentler."
Haas had never broken 70 before in 16 previous rounds at Augusta but recovered from a bogey on the first with six birdies, including from five feet on the 18th after also dropping a shot on the 17th.
"I knew about that stat before the round so to shoot in the 60s feels great," Haas said. "There is a lot of golf left but I'm ecstatic with today."
Playing alongside Scott, England's Matt Fitzpatrick got off to a nightmare start with a double-bogey six, the US Amateur champion driving into trees and then pitching over the green with his third shot.
However, the 19-year-old from Sheffield hit back with a birdie on the second and remained one over par until bogeys on the 13th, 14th and 17th meant an opening 76.
"I think he played really well," Scott said of Fitzpatrick. "Obviously it was a nervous start and I stood there and thought, 'That's what I looked like many times playing the first hole at the Masters.
"But he did hole a great putt for double bogey and that's exactly what I said to him. I said, "Great putt, get going now." And he calmed down and he birdied the next and he played fine."
Fitzpatrick added: "I felt like I played all right. I played well for nine after the first hole but the back nine just trickled away a little bit. Just trying too hard, a few loose shots and it cost me, really.
"When the starter said you will be marking Adam's card I got a little bit excited, but Adam's a great guy and a fantastic player."