As mentioned here earlier this week, the club initially got the date wrong for Ben Hogan's famous 1-iron shot when it installed a marker on the 18th fairway in 2000.
Well, Merion also shanked its other historic plaque.
Bobby Jones clinched his unprecedented and still unequaled Grand Slam by winning the 1930 U.S. Amateur on Merion's 11th hole. Much later a commemorative plaque was affixed to a boulder and placed alongside the 11th tee.
It originally read: "On Sept. 27, 1930, and on this hole, Robert Trent Jones Jr. completed his 'Grand Slam' by winning the U.S. Amateur Championship."
Unfortunately, "Robert Trent Jones Jr." did no such thing.
Robert Trent Jones Jr. and his father, Robert Trent Jones, are both well-known golf architects. It was, of course, Robert Tyre Jones Jr. who won the grand slam.
So, as it was forced to do with the Hogan marker, Merion ordered a new brass strip with the golfer's correct name and installed it atop the erroneous reference.
God help Merion if Yoshinobu Tsukada wins the 2013 Open.
In case this will be your first visit to a professional golf tournament, here are some terms you're likely to encounter and their meanings:
All Square: A foursome of Steve Stricker, Zach Johnson, Lee Westwood, and David Toms.
Front Nine: The site of Merion's new swimming pool.
Fade: What Sergio Garcia tends to do in the fourth round of majors.
Flyer, Eagle: Two things you don't have to worry about in a playoff.
Sand Wedge: Cheesesteak or hoagie.
Short Game: A dwarf deer.
Giving 'Em Fitz:
5 things overheard
1 Man to a friend: "I'm telling you, the greatest ball-striker of all time was a guy named Mo Gordon."
2 Man to a friend as they surveyed the Open's Spectator Square: "This is unbelievable. We're 20 feet in the air and walking on carpet."
3 One man to a friend who was showing him the giant golf ball he'd purchased in the merchandise tent: "What the hell do you need a volleyball for?"
4 Wife yelling loudly to her husband as she dashed off: "I'm going in there to get that thing."
Even-louder husband: "Jean! Get one for me too!"
5 One man to a friend who was admiring the iconic photo of Ben Hogan at Merion: "Prettiest swing ever, that Sam Snead."
5 things not overheard
1 "The Rose Tree parking lot has not reopened. We're urging all spectators to utilize SEPTA or the United States Coast Guard."
2 "A friend of mine spotted Boo Weekley at the Bryn Mawr Library last night."
3 "Attention, Tiger Woods: You've left the lights on in your Dodge Dart."
4 "Too bad the Phillies aren't in town this week."
5 "If I lived in one of those houses along the 14th hole, I wouldn't let them park trucks in my driveway, $45,000 or no $45,000."
Contact staff writer Frank Fitzpatrick at email@example.com. Follow on Twitter @philafitz.