# MLB's Rubbing Mud - Magic or Science? **URL:** \ **Category:** The Game Room\ **Tags:** baseball-mlb\ **Created:** [December 13, 2024, 12:44pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602 "2024-12-13T12:44:07Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [December 13, 2024, 12:44pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/1 "2024-12-13T12:44:07Z")
It’s awhile yet until spring training. So here’s something for science-minded MLB fans to think about. This article showed up in my feed this morning: > **[Geoscientists Demystify Baseball’s Magic Mud - Eos](https://eos.org/articles/geoscientists-demystify-baseballs-magic-mud)** > > Taking baseball’s mysterious Rubbing Mud into the lab revealed no magic ingredients—but plenty of useful natural properties from geomaterials. What I found interesting (and slightly suspicious) was the comment by one of the scientists that in general muds are very sensitive to the mix of grain sizes and the moisture level. Which makes me wonder how this secret location on some minor river in NJ can so consistently deliver the same mud year in and year out. And in a fairly hefty quantity. For round numbers 250K baseballs are used to play the games of a season of MLB. Then there’s all the balls used in pregame practice /warm-up sessions during the year, bullpen warm-ups, pre-season play, and all of the minor leagues too. I’ll wag that at the same number of balls again, so 500K total per year. Even at (WAG) half an ounce of mud per ball it adds up. That WAG gets us 15K# of mud. so 7.2 tons of mud. About 1 small dump truck’s load. Compared to mining for iron, that’s nothing. But for some little stream / riverlet to produce that much mud and to be able to withstand having that much removed and it just keeps making more of the same with high repeatability? Color me a bit confused. The lore is the magic mud is just scooped out by hand or small shovel and dumped into containers with zero processing. Color me a bit skeptical about that. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [December 13, 2024, 2:15pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/2 "2024-12-13T14:15:02Z")
Since the location of the mud mine is secret we don’t know that it’s located in a river or exposed to moving water, or that more of it is forming in the ground. There are similar long lasting natural deposits of clay and mud. Some mud deposits produce fine grained abrasive material not found elsewhere. I’m still a bit skeptical myself that no other material can provide the same properties for rubbing on baseballs. ---
**Author:** ![BobLibDem](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/boblibdem/32/3149_2.png) [@BobLibDem](https://boards.straightdope.com/u/BobLibDem)\ **Post date:** [December 13, 2024, 2:18pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/3 "2024-12-13T14:18:03Z")
What I don’t get is that they go through all the trouble of mudding up the balls to take the shine off, but in game play it’s like “OH MY FUCKING GOD! THE BALL TOUCHED THE GROUND! WE MUST TOSS THE BALL OUT AND NEVER USE IT AGAIN!” ---
**Author:** ![AlsoNamedBort](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alsonamedbort/32/3213_2.png) [@AlsoNamedBort](https://boards.straightdope.com/u/AlsoNamedBort)\ **Post date:** [December 13, 2024, 2:23pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/4 "2024-12-13T14:23:56Z")
> [@TriPolar](#): > > I’m still a bit skeptical myself that no other material can provide the same properties for rubbing on baseballs. Considering how superstitious baseball players are, I’m sure if they switched to something else they would immediately start complaining that the ball is behaving wrong. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [December 13, 2024, 2:26pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/5 "2024-12-13T14:26:17Z")
> [@TriPolar](#): > > Since the location of the mud mine is secret we don’t know that it’s located in a river or exposed to moving water, or that more of it is forming in the ground. Here’s a [gift link](https://www.nytimes.com/2022/07/26/sports/baseball/baseball-mud-supplier.html?unlocked_article_code=1.hE4.IvWU.b28y0yV5QrPr&smid=url-share) to an article about the guy who supplies the mud to Major League Baseball, with a photo showing him collecting it. The site is along a “Delaware River tributary.” ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [December 13, 2024, 2:36pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/6 "2024-12-13T14:36:31Z")
> [@Dewey\_Finn](#): > > Here’s a [gift link](https://www.nytimes.com/2022/07/26/sports/baseball/baseball-mud-supplier.html?unlocked_article_code=1.hE4.IvWU.b28y0yV5QrPr&smid=url-share) to an article about the guy who supplies the mud to Major League Baseball, with a photo showing him collecting it. The site is along a “Delaware River tributary.” And we still don’t know because it’s secret. That guy could be digging up mud from a lot of different places. How many samples have been analyzed? How much scientific testing has been done on baseball player’s ability to tell whether or not the magic mud makes a difference as opposed to: > [@AlsoNamedBort](#): > > Considering how superstitious baseball players are, I’m sure if they switched to something else they would immediately start complaining that the ball is behaving wrong. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [December 13, 2024, 3:00pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/7 "2024-12-13T15:00:05Z")
> [@Dewey\_Finn](#): > > > [@TriPolar](#): > > > > Since the location of the mud mine is secret we don’t know that it’s located in a river or exposed to moving water, or that more of it is forming in the ground. > > Here’s a [gift link](https://www.nytimes.com/2022/07/26/sports/baseball/baseball-mud-supplier.html?unlocked_article_code=1.hE4.IvWU.b28y0yV5QrPr&smid=url-share) to an article about the guy who supplies the mud to Major League Baseball, with a photo showing him collecting it. The site is along a “Delaware River tributary.” Good cite. There was also one episode of one of those Discovery Channel (or similar) fake archeology / discoverer shows where the host goes to famous locations and finds stuff. In an episode I watched several years ago (so no cite) the host was taken to the secret mud site and watched the mud company owner scooping the mud out of the “beach” where the bank meets the shallows and into a pail while we all got to watch too. IIRC this was at a bend in a generic stream which was 10-20 feet across and ankle to knee deep. In an otherwise unremarkable temperate forested area. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [December 13, 2024, 3:02pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/8 "2024-12-13T15:02:46Z")
> [@BobLibDem](#): > > What I don’t get is that they go through all the trouble of mudding up the balls to take the shine off, but in game play it’s like “OH MY FUCKING GOD! THE BALL TOUCHED THE GROUND! WE MUST TOSS THE BALL OUT AND NEVER USE IT AGAIN!” A scuffed ball can be exploited by the pitcher to get extra movement. That’s why pitchers constantly try to alter the ball illegally. Look what Greg Maddux did with a scuffed ball before they were routinely removed. > **[The SECRET behind Maddux's FILTHIEST Pitch EVER! #mlb](https://www.youtube.com/watch?v=dSzExKtBNtA%2F)** > > Greg Maddux gives the story behind his filthiest two seamer ever.Maybe the filthiest two seamer ever thrown.#baseball #sports Shop now at PitchingNinja.com !... ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [December 13, 2024, 3:20pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/9 "2024-12-13T15:20:32Z")
> [@TriPolar](#): > > I’m still a bit skeptical myself that no other material can provide the same properties for rubbing on baseballs. It’s not so much the rubbing properties, it’s the fact the mud doesn’t discolor the balls. I’m sure by now, if there was something else that worked, MLB would have found it. ---
**Author:** ![Procrustus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/procrustus/32/2994_2.png) [@Procrustus](https://boards.straightdope.com/u/Procrustus)\ **Post date:** [December 13, 2024, 3:24pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/10 "2024-12-13T15:24:16Z")
> [@running\_coach](#): > > A scuffed ball can be exploited by the pitcher to get extra movement. That’s why pitchers constantly try to alter the ball illegally. Yet it’s typically the catcher that discards the scuffed ball. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [December 13, 2024, 3:34pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/11 "2024-12-13T15:34:56Z")
> [@LSLGuy](#): > > Good cite. There was also one episode of one of those Discovery Channel (or similar) fake archeology / discoverer shows where the host goes to famous locations and finds stuff. Dirty Jobs/Mike Rowe did an episode with them. ---
**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\ **Post date:** [December 13, 2024, 3:40pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/12 "2024-12-13T15:40:22Z")
> [@LSLGuy](#): > > Even at (WAG) half an ounce of mud per ball it adds up. That WAG gets us 15K# of mud. so 7.2 tons of mud. About 1 small dump truck’s load. A half ounce is a lot. The baseball itself is only 5.25 ounces, so an extra half ounce is huge. According to this article, they gather about a tenth of your estimate. [Rubbing Mud](https://www.nbcnews.com/business/business-news/baseball-has-dirty-little-secret-lena-blackburne-rubbing-mud-n226541) ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [December 13, 2024, 3:43pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/13 "2024-12-13T15:43:29Z")
There could be a large deposit of consistent mud adjacent to river that is not the result of recent silt deposits. The mud would be softer and easier to collect alongside the river because it’s wet. At the same time it increases the possibility that the mud does not have a consistent mix of constituent ingredients because other silts have mixed with it from water overflowing the bank many times over many years. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [December 13, 2024, 4:04pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/14 "2024-12-13T16:04:40Z")
> [@Joey\_P](#): > > Dirty Jobs/Mike Rowe did an episode with them. That was almost certainly it. I was an avid fan of _Dirty Jobs_. Thank you. > [@Cheesesteak](#): > > A half ounce is a lot. The baseball itself is only 5.25 ounces, so an extra half ounce is huge. Good cite Thank you. I wasn’t trying to suggest they left a half-ounce of mud adhering to the ball. Sorry to be unclear. My estimate started from a line I read that they use a lump of mud “the size of a finger” per ball. Most of which _I assumed_ ends up as waste. In any abrasive situation, whether we’re exfoliating a face, scuffing a baseball, or grinding away metal in a factory, a lot more abrasive is consumed than remains attached to the finished product. Where I probably really erred was in assuming the residue of the lump they rub on one ball was just dumped as now impure. Whereas if much of the lump right goes back into the mud bucket to be scooped again on another ball, the consumption per ball could be 1/10th to 1/20th as much. ---
**Author:** ![puzzlegal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/puzzlegal/32/3827_2.png) [@puzzlegal](https://boards.straightdope.com/u/puzzlegal)\ **Post date:** [December 13, 2024, 4:16pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/15 "2024-12-13T16:16:56Z")
> [@LSLGuy](#): > > What I found interesting (and slightly suspicious) was the comment by one of the scientists that in general muds are very sensitive to the mix of grain sizes and the moisture level. Which makes me wonder how this secret location on some minor river in NJ can so consistently deliver the same mud year in and year out. And in a fairly hefty quantity. I think it’s unremarkable that a deposit of mud would have a consistent mix of grain sizes. And they may wet the mud prior to application, to give it a consistent amount of moisture. I doubt this particular mud is magic, and couldn’t be replaces with some other mud deposit. But I don’t find it suspicious that it gives consistent results that they are happy with. ---
**Author:** ![Munch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/munch/32/5281_2.png) [@Munch](https://boards.straightdope.com/u/Munch)\ **Post date:** [December 13, 2024, 4:30pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/16 "2024-12-13T16:30:19Z")
> [@LSLGuy](#): > > Whereas if much of the lump right goes back into the mud bucket to be scooped again on another ball, the consumption per ball could be 1/10th to 1/20th as much. It’s barely a lump - it’s enough to get your hands dirty with it, and then diluted. [![](https://img.youtube.com/vi/mU4877RdQFs/maxresdefault.jpg "Behind the Scenes: Prepping game balls") ](https://www.youtube.com/watch?v=mU4877RdQFs) ---
**Author:** ![TroutMan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/troutman/32/6721_2.png) [@TroutMan](https://boards.straightdope.com/u/TroutMan)\ **Post date:** [December 18, 2024, 9:51pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/17 "2024-12-18T21:51:07Z")
> [@Procrustus](#): > > Yet it’s typically the catcher that discards the scuffed ball. That’s only because he’s the one who just caught it. He knows the ump is going to discard it, so it saves a step. Sometimes you’ll see the catcher hand the ball to the ump for inspection after it hits the ground. I have never once seen the ump keep the ball in play after looking at it. I’d assume most catchers realize there’s not much point to that charade. (Or if you want to think the worst of everyone, the catcher is discarding the ball to avoid the ump noticing some illegal alteration the pitcher made to it.) ---
**Author:** ![mattgg](https://avatars.discourse-cdn.com/v4/letter/m/ccd318/32.png) [@mattgg](https://boards.straightdope.com/u/mattgg)\ **Post date:** [December 26, 2024, 10:50am UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/18 "2024-12-26T10:50:22Z")
> [@TroutMan](#): > > Sometimes you’ll see the catcher hand the ball to the ump for inspection after it hits the ground. I have never once seen the ump keep the ball in play after looking at it. I’d assume most catchers realize there’s not much point to that charade. I can’t recall an ump handing the same ball directly back to the catcher but it’s not uncommon for an ump to put the ball back in his bag to be used again. I think they always hand the catcher a new ball before inspecting the one they received from the catcher just to get a ball back to the pitcher as quickly as possible. The ump can then take a couple of seconds to decide whether to toss the game-used ball or keep it. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [December 26, 2024, 12:42pm UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/19 "2024-12-26T12:42:24Z")
> [@LSLGuy](#): > > For round numbers 250K baseballs are used to play the games of a season of MLB. Then there’s all the balls used in pregame practice /warm-up sessions during the year, bullpen warm-ups, pre-season play, and all of the minor leagues too. I’ll wag that at the same number of balls again, so 500K total per year. I think you’re over estimating the number of balls. I believe they reuse the balls rejected in games during practice and some of the other uses you mention. Also, they aren’t as picky about rejecting scuffed balls in the minors as they are in the majors. The lower the minor league, the less picky. As far as rejecting balls, they don’t always reject balls that have hit the ground. It’s mainly when the ball hits the ground during a pitch and maybe ground balls (I’m not sure about them). If someone just drops it, they don’t reject it. It’s the high speed impact that scuffs the balls. ---
**Author:** ![Zakalwe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zakalwe/32/270_2.png) [@Zakalwe](https://boards.straightdope.com/u/Zakalwe)\ **Post date:** [December 29, 2024, 1:28am UTC](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602/20 "2024-12-29T01:28:10Z")
My favorite story about this is A.J. Pierzynski getting tossed from a game. Pitch came in, ump called it a ball (it was IMHO), A.J. turns around and hand the ball to the umpire. Ump asks him why he needs a new ball, and A.J. replies “I need one you can fucking see.” Ejected. In a post-game presser, A.J. said he’d always wanted to say that and it seemed like the right time. [Next page](https://boards.straightdope.com/t/mlbs-rubbing-mud-magic-or-science/1011602.md?page=2)