It's a magic number in golf, one that many players have had in their sights over the years, at the Masters, the U.S. Open, the British or the PGA Championship, only to somehow let it get away.
This was one of three birdies in a row and four in a span of five holes on the front nine.
The 2013 Open champion came within inches of becoming the first ever player to shoot 62 in a major championship when his birdie putt at the last lipped out, leaving him to settle for an eight-under-par round instead.
Patrick Reed took the clubhouse lead midway through the first day of the British Open, posting a score of five under, as early favourites climbed close to him before sliding back down.
The day began with local favourite Colin Montgomerie hitting the opening drive, his first appearance at the Open in six years and what may well be his last.
The forecast for Friday's second round is grim, with rain coming and fierce winds expected to whip up off the Irish Sea.
Like most players will this week, he fared better on the easier opening nine, where the wind is generally favorable, before grinding through the inward nine holes, which are largely into the teeth of the winds. "It breaks to the left and then straightens out.I don't know what to say". I have been working hard this year to get my swing on plane and today was the day when I did not have a lot of stress and was able to control the golf ball throughout the round.
The International Golf Federation, run by former R&A chief Peter Dawson, took over Open week on Monday to announce that Olympic qualifying had ended and that Spieth (along with Rory McIlroy, Jason Day, Dustin Johnson and 16 other men) was not playing.
"All these highlights", he said, speaking of his round, "and I feel like crying".
Americans held seven of the top eight places on the leaderboard when Mickelson finished at 18. "I knew that was where the majority of the scores were going to come from". I had that surge of adrenaline that I had just shot 62 ... and then I had the heartbreak that I didn't and watched that ball lip out.
On the Postage Stamp, his tee shot landed within six feet of the pin.
Els was inside Mickelson's ball but volunteered to putt first to clear the stage for another Phil-the-Thrill moment in the making.
The five-time Major champion made a mockery of Troon's brutal back nine but could not find the bottom of the cup from 15feet for a 62 at the 18th. Mickelson has a great chance to put things nearly out of reach for younger stars like Rory McIlroy and Jordan Spieth, who had likely left the golf course feeling pretty decent about rounds of 2-under and even par, respectively, earlier in the day.
Spieth let it slip through his fingers last year at St. Andrews going for his third straight major, and he wound up holding it later that evening - but only because he was with Zach Johnson, the champion golfer of the year, when it was over.
The mild weather meant a few players scored well, including a host of Americans, the nation with the best record in The Open at Royal Troon. But two under par, something in the 60s, it's a solid start. And in the ideal conditions at Royal Troon, he shot 73.
No wonder Montgomerie was happy to finish with an even-par 71.