A ban would stop players from using long putters - also known as belly putters, chin putters and broomhandle putters - in just over three years.
Though the clubs themselves will not become illegal, they will become effectively useless since they are only effective when anchored to part of the player's body. Banning the stroke but not the clubs is like telling boxers they can use boxing gloves, but only if they don't wear them on their hands.
Among the players affected will be reigning Open champion Ernie Els, 2012 US Open champion Webb Simpson and 2011 US PGA champion Keegan Bradley.
A period of consultation with the industry will take place before any ban is confirmed, but R&A chief executive Peter Dawson sounded confident that the move will go ahead.
"We believe we have considered this issue from every angle but given the wide ranging interest in this subject we would like to give stakeholders in the game the opportunity to put forward any new matters for consideration," he said Peter Dawson.
We take a look at the why the clubs appeared in the first place, and why they are now set to be effectively banned.
What are long putters for?
The idea is that players can wedge long putters against some part of their body to keep a firm point from which to swing, something which helps many players who suffer from the yips, which are involuntarily nervous jerks or twitches. It's the idea of anchoring the club to part of your body which has been outlawed, not the clubs themselves.
Why are they being banned?
It's about preserving the integrity of what is and what isn't a golf shot. As the R&A and USGA said in their joint statement, "Throughout the 600-year history of golf, the essence of playing the game has been to grip the club with the hands and swing it freely at the ball. The player's challenge is to control the movement of the entire club in striking the ball, and anchoring the club alters the nature of that challenge. Our conclusion is that the Rules of Golf should be amended to preserve the traditional character of the golf swing by eliminating the growing practice of anchoring the club."
How long have long putters been around?
Since the mid-1980s. Sam Torrance was the first to make them famous, with the "chin putter". Belly putters came later, and have been a much bigger success since most players find them far easier to adapt to. They are primarily responsible for the soaring popularity of long putters in the last 10 years, with many young players now coming through having never used any other method.
If they've been around for nearly 30 years, why the ban now?
In the past, long putters were seen as the mark of a desperate golfer trying to prolong a career. Nobody wanted to kick those players when they were down, and considering that nobody had ever achieved any consistent world-beating success with the long clubs there wasn't much of an issue.
All that changed at the 2011 US PGA Championship, where Keegan Bradley became the first player ever to win a Major using a long putter. Since then, Webb Simpson (at the 2012 US Open) and Ernie Els (at The Open Championship) have both won Majors with long putters. In the case of Els, the man he beat down the stretch - Adam Scott - was also using a long putter.
Those players won't be too happy...
Absolutely not. "A lot of us feel strongly about the hours of practice we've put in that they're saying is basically for nothing now," said Bradley recently, while Els added that the R&A and USGA, "are going to have a couple of legal issues coming their way... we are talking about people's livelihoods."
What are their arguments?
The very best putters in the world - statistically speaking - still use short putters, and it's commonly felt that long putts (from over 20ft) are much easier with a short putter than a long one. And given the fact that they have been so legal for so long, many will argue that a ban is harsh and unfair.
Will a law suit really happen?
The big worry for the R&A and USGA is that the equipment manufacturers will act to protect their colossal profits (as they did in other equipment bans in the past), but considering that the clubs themselves have not been banned that may not be an issue. However, a court might be persuaded otherwise: the ban is effectively on the clubs themselves regardless of how it's worded since long putters are utterly useless unless they are anchored against the body.
Bradley, meanwhile, has proposed that a potential "restraint of trade" law suit could be in the pipeline. Given that we're ultimately talking about a game whose rules are already quite often confusing and illogical, it seems hard to imagine a court opening that particular Pandora's box.
So what will happen?
In all probability a ban will come in and everybody will simply get on with it. The elite players will get used to it and the equipment manufacturers will be happy to sell millions of new putters to those who use the longer versions.
The reality is that most players use 'normal' putters, and therefore most players will back the ban. In addition, similar bans have been imposed in the past - such as the outlawing of Sam Snead's croquet-style putting stroke in the 1960s. Further back in the game's past, players have been banned from scooping or flicking their ball.
Els, now a proponent of long putters, admitted after winning The Open he considers long putters "a form of cheating."
"Nothing should be anchored to your body and I still believe that," he said "But as long as it's legal, I will keep cheating like the rest of them."
He may be talking about fighting the ban now, but those words will surely come back to haunt Els.