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Engineering professor tests for juiced balls

With all the homers, MLB hires Jim Sherwood to test its baseballs to see if they meet specifications.

As a baseball fan, Jim Sherwood doubts a juiced ball is to blame for the increase in home runs this season.

As a scientist, he wants to know for sure.

A mechanical engineering professor at the University of Massachusetts' Lowell campus, Sherwood has been commissioned by Major League Baseball to test the ball to make sure it meets the specifications in the rule book.

"As a fan, it's exciting to see the home runs. But I guess you want to see the integrity of the game maintained as it had been in the past," he said. "We're going to answer whether the ball is part of the problem or not, whether it's hotter than it's supposed to be."

Batters hit a record 931 homers in April 105 more than in the first month of the 1996 season. Not including the four hit in March, there has been 2.56 homers per game this year, an increase of 15 percent from last April's 2.22.

Although smaller ballparks, bigger hitters and weaker, expansion-era pitching might explain much of the surge, there are those who suspect that something more sinister is afoot.

While denying the ball has changed, baseball officials on Monday will be in Costa Rica to tour the Rawlings plant where it is made.

"We know what they're going to find out: The ball hasn't changed," said Ted Sizemore, who played with Los Angeles, St. Louis, Philadelphia and Boston before becoming a senior vice president at Rawlings.

"Nothing's changed in the 16 years I've been here, and people that have been here before me tell me Major League Baseball has never asked them to change the ball. I'm not down at the factory every day, but I can tell you that everything is the same."

Rawlings has been the majors' exclusive supplier since 1977, making each one with a cork center surrounded by four different windings of yarn: four-ply gray wool, three-ply white wool, three-ply gray wool and finally a thinner cotton yarn that gives the ball a smoother surface. It is weighed and measured at each step.

The leather cover _ the switch from horsehide to cowhide came in 1974 _ is inspected for 17 potential imperfections, from stretch marks to scars, and then is stitched by hand. The ball is checked to make sure it fits the major-league specifications of 5 ounces, and 9 inches around.

The ball also is required to have a specific hardness, or "coefficient of restitution," which is measured by firing it at a piece of northern white ash 2{ inches thick. The ball's speed is measured as it comes out of the gun, and it must rebound at 54.6 percent its original speed, plus or minus 3.2 percent. The ball also must hold its shape within 0.08 of an inch after being subjected to 65 pounds of pressure.

One thing Sherwood can't do is compare the balls to those used in the past.

"The materials of the baseballs change, temperature and humidity, these affect the ball. You can't really go backwards unless we find some preserved baseballs," he said. "We're starting to track a history of the baseball."

Sherwood, who also certifies aluminum bats for the NCAA, said he expects to have a report by mid-June.

Sizemore said he is less concerned about the test results than the perception that baseball is fiddling with it to please homer-happy fans.

"Being a former player, and a traditionalist, I would never do anything to change the ball," he said. "I can sit back and laugh to myself and say, "I know this ball hasn't changed.' But I have to defend that. So we test and retest. That's all we can do. And we're the best at it in the world."

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