A member for a half-century, he could walk there from his home opposite the second hole. Davis, who owned an insurance agency, could tailor his schedule to his golf. On weekends, he typically played 72 holes at Merion. Three times a club champion, he had a handicap that fluctuated between scratch and a 3.
But for the thousands of rounds he played there, only one, on June 4, 1964, was unparalleled.
Merion, of course, wasn't set up for a U.S. Open that day. The rough was thinner. The holes were shorter. The greens were slower.
Still, the scorecard Davis turned in looked like one from a miniature golf round. Playing from the white tees, he recorded 10 consecutive 3s on the toughest part of the course, holes 8 through 17.
"I truly believe this was one of the greatest rounds Merion has ever witnessed," Bill Arnold, one of Davis' three playing partners that day, wrote in a club publication later that month.
Davis, who finished with a 5-under-par 65, nearly made it 11 3s in a row, but, as Arnold noted, a 30-footer for birdie lipped out on the brutally difficult 18th.
A framed copy of that scorecard now hangs in Merion's men's locker room. The Spalding Cash-In putter Davis used then and throughout his life resides in Merion's archives, alongside clubs used by such legends as Ben Hogan and Bobby Jones.
Those few members and caddies old enough to recall it still discuss the memorable round. But Davis rarely did during the last decades of his life.
"People always reminded him of it," his son said. "But he was very humble and didn't like to talk about it. I think that after a while he got tired of hearing about it."
It was only nine days after former President Eisenhower had played in a Merion exhibition with Arnold Palmer that Davis, Arnold, Lee Keeler, and Bill Ginn teed off on a Thursday afternoon.
Nothing that happened early that round hinted at what was to come.
According to Arnold's account in the club publication, Fore, Davis had a routine par on the first hole. Then, with his house visible just across Ardmore Avenue, the insurance agent three-putted on the par-5 second for a double-bogey.
Davis managed pars on the next five holes. Then came the remarkable run of 3s. Such a streak was possible, in part, because Merion has only two par-5s, none after the fourth hole.
"So there aren't many courses where you can even think about doing something like he did," said Lee Davis, 55, a Wynnewood resident and Merion member.
He birdied the eighth and parred the par-3 ninth for a front-nine total of 37. His dead-on approach shots on the pair of short par-4s that followed, 10 and 11, left him with tap-in birdie 3s on each.
He sank an 18-footer for birdie on 12, two-putted for a par on 13, and made a 9-footer for his 3 on 14. Now he was heading into the meat of Merion. Surely, his kibitzing partners thought, the streak would end there.
"Needless to say Andy was not treated like a baseball pitcher about to spin a no-hitter," Arnold wrote. "He was constantly reminded of his great string of 3s. However, from the 13th on he hit the ball more solidly than before."
On the uphill par-4 15th and the famed quarry hole at 16, Davis made 12-footers for birdies. His par at 17, the long par-3, made it 10 3s in succession.
The streak finally ended at 18, where his lengthy putt hung on the lip. He tapped in for a par-4 and an astounding back-nine total of 28.
The official course record at Merion is 64 by Art Lackey Jr. at the 1950 U.S. Open and Ben Crenshaw in the 1981 event. Comparing those rounds to Davis' is, of course, apples to oranges.
According to his son, no one is certain if Davis' 10 consecutive 3s has ever been duplicated or surpassed at Merion.
"But I'm not sure it's ever really been looked into either," he said.
Last year, Lee Davis donated his father's putter to the club's archives. It had been sitting in the son's garage for nearly 20 years.
"I actually tried to putt with it a couple of times," he said, "to no success."
Davis, who later spent six months each year in Florida and got to know and golf with Jack Nicklaus there, played Merion well into his 70s. His widow remains a member. He died in 1995. The three men who played with him that day are dead too.
"Late in his life he used to joke that the only people who knew him anymore were the caddies," Lee Davis said. "It's funny, but I'll bet you 10, 20, 30 times since then I've been out and I've run into caddies. When they find out who I am, they all say, 'My God, I remember Andy Davis.' They never forgot that round."
Contact Frank Fitzpatrick at firstname.lastname@example.org. Follow on Twitter @philafitz.