Former baseball slugger Sammy Sosa didn’t just get bigger over the years, he also might have wanted to show his fans how big he was getting.

It turns out Sosa had his jerseys tapered around his arms for a period of years. A study of photo archives suggests Sosa’s jerseys were tailored with elastic inside the arms from 2002-2004, while he was playing with the Chicago Cubs.

Sosa’s custom ordering came to light thanks to pictures of an authentic Sosa jersey that is currently being auctioned off by Hunt Auctions. The jersey, advertised as being used by Sosa for the game he hit home run No. 470, was from the 2002 season.

CNBC confirmed through a source that Sosa did indeed ask for the elastic arm tapering for at least the 2002 season. The source said that he could not remember another player that asked for this specification.

“I don’t know why it would be tapered like that other than it being a purely cosmetic change so that people could see his muscles,” said David Hunt, president of Hunt Auctions. “There doesn’t seem to be any other reason why he’d do it.”

Source: Hunt Auctions Sammy Sosa Cubs Jersey Back

Source: Hunt Auctions Sammy Sosa Cubs Jersey Front

Hunt said he has seen elastic on the sleeves of jerseys for running backs and wide receivers, but that is done so that people can’t grab the sleeves to tackle them.

Hunt did say slugger Jimmy Foxx, who was nicknamed “The Beast,” was known to cut off his sleeves presumably so that the opposing pitcher would be intimidated by his arms.

Sosa’s agent Adam Katz could not be immediately reached for comment.

Current bidding on the jersey is $450. The estimated price the jersey will go for by the time it closes on July 14 is $1,000. Hunt says that’s typical for players associated with performance-enhancing drugs. The New York Times reported last week that Sosa tested positive for performance-enhancing drugs in 2003.

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