• Complete Arizona Fall League coverage
For three games last week at Salt River Fields, MLB tried out a Rawlings baseball covered with a proprietary chemical designed to give it a tackier feel than a standard ball. The idea is to eliminate the need to rub down balls before the game with a special mud.
Three games is too small a sample size from which to draw any wide-ranging conclusions, of course. Furthermore, the experimental baseballs were a version of the Major League ball rather than of the Minor League ball normally used in AFL games and to which prospects are much more accustomed.
From his perspective, Salt River Rafters catcher Grayson Greiner (Tigers) thought the experimental ball was a little slicker than usual. He said he didn't have any problems with throwing accuracy, though he made sure to get a tighter grip than usual.
Greiner said the balls were brighter (because they weren't rubbed down with mud) and easier to see for hitters. He thought pitchers had a bit more life on their sinkers and cutters, and a little more late bite on breaking pitches. He didn't note anything different about the spin on various pitches, but he thought the ball carried better, which could be the result of the flatter seams on Major League balls.
"As a hitter, I liked them because they traveled further and you could see them better," Greiner said. "From the pitcher's standpoint, they probably get a little more movement on it."
Glendale Desert Dogs right-hander Austin Voth (Nationals) threw five scoreless innings and didn't issue a walk with the experimental ball, yet he didn't like it. He thought the ball was too slick and more tightly wound than usual.
"They were definitely different," Voth said. "Those weren't my favorite. It felt like a big league ball not rubbed up and it felt like it was slippery. Every ball I had, I rubbed it up with dirt. And after that, if felt about the same."
According to Major League Baseball, the integrity and performance of the baseball hasn't changed as measured through many quality control tests and empirical data points. MLB will continue to evaluate the ball after the AFL season, though no further in-game testing is planned.
Jim Callis is a reporter for MLB.com. Follow @jimcallisMLB on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.