Robert Kraft, with his son Josh, said of Aaron Hernandez: “If this stuff is true, then I’ve been duped and our whole organization has been duped.” (Charles Krupa / AP)

New England Patriots owner Robert Kraft spoke for the first time today about the murder charge the team’s former tight end, Aaron Hernandez, is facing and acknowledged the Patriots “made a mistake and are facing it head on.”

“If this stuff is true,” Kraft said, “then I’ve been duped and our whole organization has been duped.”

Hernandez is being held without bail and has pleaded not guilty to murder and gun-related charges in connection with the death of Odin Lloyd on June 17. About 90 minutes after his arrest, Hernandez was released by the team, which further expunged him from its history by holding a jersey exchange over the weekend in which fans turned in about 2,000 of his No. 81 for another jerseys.

“You can be sure we’ll be looking at our procedures and auditing how we do things,” Kraft said (via ESPN Boston’s Mike Reiss) in a meeting with Reiss and reporters from the Boston Globe and Boston Herald in his office.

Kraft was in Europe as the Hernandez investigation was unfolding and he summoned the media on his first day back at work. “My heart goes out to the Lloyd family,” he said. “I feel bad that someone connected to our organization is connected to this.”

Kraft said the Patriots had no advance knowledge that Hernandez would be charged with murder when they released him. Nor did he see any troubling signs from the former tight end. Kraft went on to share a letter Hernandez wrote him before the 2010 draft in which he wrote of his alleged marijuana use at the University of Florida and agreed to bi-weekly drug tests as a rookie.

“When he was in our building, we never saw anything where he was not polite. He was always respectful to me,” Kraft said. “We only know what’s going on inside the building. We don’t put private eyes on people.”

Last summer, the Patriots signed Hernandez to a contract extension that could have been worth up to $40 million and Hernandez donated $50,000 to the Myra Kraft Giving Back Fund, named in honor of the owner’s late wife.

“He spoke to me about wanting to be a role model in the Hispanic community,” Kraft said. “… I believed him. … He knew how to push my buttons.”

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