What is a mud ball? Explaining the PGA Championship's golf rules controversy

New York Times

15-05-2025

CHARLOTTE, N.C. — They drive professional golfers up the wall. They're highly unpredictable — unfair, depending on who you ask. You never know when you're going to get one or how bad it's going to be.
They're 'mud balls,' the bain of any pro golfer's existence.
They've become a hot topic already this week at the PGA Championship at Quail Hollow, with two of the top-three ranked players in the world choosing to complain about championship officials letting them happen. To hear Scottie Scheffler and Xander Schauffele describe the controversy, the PGA is at stake with each fleck stuck to a once-pristine golf ball.
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What is a mud ball, why do they happen and what can players do to combat their devious effects?
When a drive lands in a wet fairway, it doesn't react as it normally would, with at least a few yards of roll. Instead, it lands, bounces once, maybe twice, and clumps of mud can start to attach to the sides of the golf ball. Or worse, that mud just splatters all over the ball's surface.
Walking up to one of your best drives of the day as it's sitting in the middle of the fairway, only to find that half of the ball is covered in mud is a disheartening ritual. At Quail Hollow, the experience was frequent throughout Thursday's first round. Heavy rainfall earlier this week soaked the overseeded ryegrass fairways, and as the course gets more traction and starts to dry up, the mud balls might get even more penal.
'They're going to get in that perfect cake zone to where it's kind of muddy underneath and then picking up mud on the way through,' Schauffele said.
The sight of a mud ball alone is vexing but it's how the mud impacts the ball flight that really gets players going. Pros hit the ball with speeds ranging from 100 mph to in excess of 180, depending on the club choice, and the added surface area caused by the mud can impact the direction that it flies.
Professional swing coach Joe Mayo, the self-proclaimed 'TrackMan Maestro' for his expertise in employing the PGA Tour-ubiquitous $20,000 launch monitor, says that mud balls are all about aerodynamics.
Tests and experiments throughout the years have proven a general principle to be true: When the mud is stuck to the right side of the ball, the ball is going to curve left. And when the mud is on the left side of the ball, the ball is going to curve right. The mismatched forces on either side of the ball cause the air to flow around it disproportionately.
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'It creates an aerodynamic effect, like a plane tilting its wings,' Mayo says. 'How does a pilot curve a plane? He just tilts the wings and it causes a pressure imbalance. So that mud is causing a pressure imbalance that pushes the ball to the left when it's on the right-hand side of the ball. And when the mud is on the left-hand side of the ball, there's a pressure imbalance pushing the ball to the right.'
A ball covered in mud all over is even worse — a 'double whammy,' Mayo calls it. The ball is not only going to potentially curve offline, it's going to fly shorter because it will lose ball speed. The mud in between the face of the club and the ball acts as a sort of pillow, dampening the interaction between the two surfaces.
Scheffler, the No. 1 player in the world, called mud balls one of the most frustrating issues a professional golfer can experience after he posted a 2-under 69 in the PGA Championship's opening round. On Thursday, Scheffler and Schauffele both found the water because of mud balls on the 16th hole. They both walked away with double bogey. Scheffler went on an uncharacteristic rant in his post-round interview about it.
'You spend your whole life trying to learn how to control a golf ball, and due to a rules decision all of a sudden you have absolutely no control over where that golf ball goes,' Scheffler said. 'But I don't make the rules. I just have to deal with the consequences of those rules.'
The thing about mud balls is that they can easily be prevented by the rules of golf.
Tournaments can choose to employ 'preferred lies,' which is a temporary rule that allows players to 'lift, clean and replace' their ball when it is in the fairway. The mud is wiped away. But it's generally understood that in major championships, the ball is never to be played 'up,' another colloquial term for the process. There's a belief system that the rule takes away from the purity of the game.The final round of the 2016 PGA Championship at Baltusrol, won by Jimmy Walker for his only major championship, was the last major round to use preferred lies.
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'When I look at golf tournaments, I want the purest, fairest test of golf, and in my opinion maybe the ball today should have been played up,' Scheffler said. 'But like I said, I don't make the rules.'
It's not a complete exaggeration. Scheffler believes that the mud on his Titleist cost him two shots on No. 16 and he's 2-under through Round 1, three strokes behind the leaders, Ryan Gerard and Cam Davis.
At last month's Masters, Jordan Spieth notably called out mud balls, claiming that they significantly impacted his weekend scoring. Apparently, suggesting Augusta National can be muddy is on the no-no list: 'It's just so frustrating because you can't talk about them here,' Spieth said. Complaining about mud balls can in some ways be seen as a jab to the golf course and its maintenance staff. But this week at Quail Hollow, the weather has made them inevitable.
You guys complain about distance. We complain about mud balls. Just kinda what we do lol
— Michael S. Kim (@Mike_kim714) May 15, 2025
To combat these types of on-course dilemmas, some players go as far as to communicate with equipment engineers and PhDs to train themselves to best evaluate scenarios like that of a mud ball. When Mayo was working with Hovland, the pair decided to call up PING's President of Engineering, Paul Wood, in the middle of the 2023 PGA Championship to help figure out how the moisture on the golf course would affect the flight of his irons. They were told that water creates different aerodynamics depending on what club you have in your hand — water causes long irons to spin more, and short irons to spin less.
But trying to mitigate the effect of a mud ball is a dangerous game. Some players preemptively try to hit tee shots lower, so the ball skips along the ground and rids itself of some mud before coming to rest. But that will sacrifice distance.
So when you get over the ball, you can try your best to predict what's going to happen, or you can just accept fate and wait to see how the ball reacts in the air. The result could be totally fine. Or it could get ugly.
And it could decide a major championship.
(Top photo of Ryan Fox: Jared C. Tilton / Getty Images)