The 5X Experiment: True Stories and Rumors Behind Spalding National and American League 5X Center Baseballs

Original article posted July 14, 2010. Updated Dec. 19, 2011, and republished here with edits and new images in 2024.

We’ve come across plenty of unusual Official Major League Baseballs recently, and this entry to the collection is no exception. Presented below is a multi-color laced (red and blue) Spalding American League Baseball – not Reach – bearing the stamped signature of Joseph Cronin.

What’s even more perplexing is the text around the Spalding stamp. “The 5x Center,” what in the world does that mean?

Could this have been a prototype baseball, or even an actual gamer? It certainly shows game use, and it did come from the estate of late Boston Red Sox executive vice president Dick O’Connell, who served in that role for the organization from 1961-1977. He also was the Sox general manager from ’65 – ’77, or so Wikipedia tells us. So there’s plenty of evidence that suggests these baseballs were at least on the field at some point during the late ’60s to early ’70s.

But it’s still likely that these 5X balls were nothing more than a failed experiment. Perhaps tested in spring training or batting practice. Or maybe they were a success? Any changes made to the design of the ball, such as the rubber pill at its core, could have taken place the following year, and would have never effected the outside of the game ball…

As far as these specific balls being used in Official MLB games, that’s still doubtful. Cronin was president of the AL from 1959-1973. Certainly well outside of the red and blue stitched Reach American League Baseball era – which included baseballs like this 1930s Harridge Reach example pictured on the right.

Additionally, lone Spalding stamps did not appear on American League baseballs until the 1975 season, which falls within the Lee MacPhail AL presidency. Though it’s possible that Spalding stamped their experimental baseballs with the regular NL and corporate Spalding stamp well before the Reach label was abandoned; the Spalding Orange Baseballs featured in our exclusive Charles O. Finley article are another example.

So if you have any information about these baseballs, please leave a comment in the comment section at the end of the article. UPDATE! 12/19/2011: A reader sent us the following picture of another 5X Spalding Major League Baseball…

This is the second Feeney version we’ve seen, the first is the gold-laced ball pictured above. (And we’ve since found a few more examples since publishing this updated article, which we’ll post below). These newly discovered Feeney 5X’s, like our AL Cronin, have red and blue laces. And this first one below is clearly used, interesting. But perhaps what’s most interesting is the product description that came with the used 5X ball – originally sold by the Cincinnati Reds team store:

“Super Scarce Rare 1972 Official Major League ‘CHARLES FEENEY’ Baseball that is still contained in its original packaging bag from the Cincinnati Reds. This genuine National League Baseball was obtained at the Reds Gift Shop in 1972. According to the Cincinnati Reds COA it reads ‘This to certify that the enclosed 5-X Experimental Baseball is one of a small number produced in 1972 for Major League Baseball. This Baseball, however, was found to be to lively & exceeded maximum velocity restrictions. It’s manufacture was discontinued. This is one of twelve 5-X Baseball being made available to collectors.’ This Baseball has multi-colored stitching.”

And now more helpful information from the forum Net54Baseball (a great vintage baseball card collectors site with an equally informative baseball memorabilia forum section). From Net54Baseball member “sphere and ash”:

The 5x baseball, so called because it was 5% livelier, was an experimental baseball. It was used during spring training in 1970 and discontinued because of concerns over the safety of both players and fans. Cronin, whose stamp appears on the ball, referred to the 5x derisively as Bowie Kuhn’s “little experiment,” and said, “I’ve seen enough of it. It should be outlawed.”

I own both American and National League 5x balls. The National League ball’s stitches are one color, though lighter than typical. Red and blue stitches would let players and umpires identify the ball immediately–an important design element given potential safety concerns.

Net54Baseball.com

So that should help end some of the speculation as to the use of these baseballs. We’ve heard similar explanations before, so I’m comfortable saying all of these versions were experimental and used for testing. We’ve also heard that some may have been tested in spring training games. Please comment below or reach out to us if you have more info or examples you’d like to share with our readers.

2024 Update: Oh we’ve found one more! From Hunt Auctions this past fall (2023), from the Doug Harvey Collection (former MLB umpire). This one would have been the most pristine example of the red/blue-laced Spalding Feeney 5X, if it hadn’t for those obnoxious sticker labels. But they do offer a little tidbit of interesting info… A specific month and year of use:

March 1969? That means this example predates the generally estimated years of manufacture and testing of the 5X, which are 1972-73 for most 5X balls. But wait… 1969 doesn’t make sense. Charles Feeney was not the National League president in March 1969. Warren Giles was, it was his final year. Feeney wasn’t even elected NL president until December 5, 1969, so there’s no way they printed his signature on experimental baseballs a year in advance, right? And he didn’t technically hold office until Jan. 1970. So whomever made those labels must have been mistaken. Anyway, always cool to find more examples of prototypes!