NEW YORK (CBSNewYork/AP) — San Diego Padres general manager A.J. Preller has been suspended 30 days without pay by Major League Baseball for his conduct in the trade of All-Star pitcher Drew Pomeranz to the Boston Red Sox.

The commissioner’s office announced the discipline on Thursday but did not elaborate on what Preller did wrong.

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ESPN’s Buster Olney reported that Preller ordered the Padres’ athletic trainers to maintain two separate files on players’ medical information — one for internal use, one for industry consumption. The trainers were told the practice was done to help better position the Padres in trades, and at least three teams were outraged the information was withheld that could have impact trade discussions, the report said.

The Padres traded Pomeranz to Boston on July 14 for right-handed prospect Anderson Espinoza.

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MLB said it conducted an investigation into the deal, interviewing individuals from both clubs, and submitted the findings to Commissioner Rob Manfred.

Padres spokeswoman Shana Wilson said the Padres have been cooperating fully with Major League Baseball’s investigation.

“There was no direction or intent on our part to mislead other clubs with respect to a player’s medical information,” she told ESPN.

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