The 113th U.S. Open Championship starts tomorrow, though not much golf will be played on Thursday with heavy rain expected most of the day. This continues a trend at Merion where nearly a half a foot of rain has fallen over the past two weeks. The U.S. Open typically features the most difficult scoring conditions of the year primarily due to a combination of course length and firmness of greens and fairways. The latter defense has been removed by the weather and the former is also missing this week, what with Merion being the shortest U.S. Open course since 2004.

Because of this, scoring is expected to be among the lowest in U.S. Open history. lists an over/under of 270.5 (9.5 under par) on the winning score. Just once has a U.S. Open participant posted a better score – Rory McIlroy’s winning 268 in 2011. 

There has been some speculation as to whether a 62, never seen in a major championship, could be shot this week. For the record, Ian Poulter and Geoff Ogilvy think not…

But a pro golfer publicly downplaying scoring conditions is as common as a newly-hired college basketball coach touting his up-tempo offense.

The good thing about this year’s U.S. Open is that scoring is expected to resemble a typical PGA Tour event. So instead of taking Poults’ word for it, we can get a handle on the chances of a low number by looking at recent history. For instance, for all PGA Tour events with a field of at least 100 golfers since the beginning of last season, the average winning score was 270.3, very close to Sportsbook’s line. In 20 of those 58 tournaments, a score of 62 or lower was shot by somebody in the field. A 63 has happened in just three previous U.S. Opens, but just over half (30) of PGA events over the past two seasons.

Winning scores on tour are not normally-distributed, however – the distribution is skewed towards lower figures. This season’s Sony Open and Phoenix Open were both won with a score of 256, which would be -24 at Merion, an unrealistic number.  If we ignore the 12 tournaments where at least ten golfers finished with a score of 270 or better, we end up with a group that has an average winning score of 272.1. The tenth-place golfer in these events had an average score of 278.6. Of these remaining 46 tournaments, eight (or 17%) had a score of 62 or less posted at some point. Eighteen (or 39%) featured a score of 63 or less. A record score might not be so far-fetched.

However, there’s some reason to be more cautious than that analysis suggests. The 2011 U.S. Open at Congressional Country Club set the standard for low scoring at a U.S. Open. McIlroy posted that 268 and 14 golfers shot better than 280. But no golfer carded a 63 and there wasn’t even a 64 in the event.

The last time the U.S. Open was played at Merion was in 1981 and David Graham posted a winning score of 273 (-7). The only score of 65 or less in that year’s event was Ben Crenshaw’s third-round 64. And of the PGA tournaments over the past two seasons, just twice was a 62 shot in a tournament where the tenth-place golfer shot 276 (-4 on a par 70) or worse, representing 32 events. Both of those cases involved a tournament that used multiple courses, with the sub-63’s shot on the easiest course. So while scoring conditions as Merion will be easy by the USGA’s standards, it will probably take even lower scoring than expected to produce a magical 62.

But on the flip side, the winning score (even if we could know that right now) isn’t a perfect predictor of the best round score, either. The previous U.S. Opens with a 63 involved final winning scores of 279 (1973), 272 (1980), and 272 (2003). The 2009 U.S. Open featured a winning score of 276, but soggy conditions for the first two rounds allowed a pair of 64’s to be shot anyway.

Despite Poulter’s protests, a 63 is a distinct possibility this week, especially if a dozen or so players finish under par. And while a 62 is a longshot, conditions are as favorable for one as they’ve ever been at a U.S. Open.