“Mad Men” star Jon Hamm finished a secret stay in rehab for alcohol abuse, TMZ said in an exclusive report Tuesday. The actor finished a 30-day program days before the final season of his hit AMC show was to premiere.

The star, 44, was admitted to Silver Hill Hospital in New Canaan, Connecticut -- a high-end facility -- at the end of February. "With the support of his longtime partner Jennifer Westfeldt, Jon Hamm recently completed treatment for his struggle with alcohol addiction. They have asked for privacy and sensitivity going forward,” Hamm’s rep said in a statement to TMZ.

Rumors swirled Hamm struggled with alcoholism after the National Enquirer ran a story in 2011 about how Hamm was professional on set but would drink to excess afterward. “On the set, Jon’s always as sober as a preacher,” a source told the Enquirer, according to Celebitchy. “But when he’s not working, he likes to cut loose with a drink or two, or more! By the end of night, he often seems blotto. His nickname is ‘Hammered.’”

“Jon’s a hell of a nice guy,” the insider said in 2011. “But his drinking has caused whispers. No one wants to see him end up in rehab.”

Hamm is arguably best known for his portrayal as Don Draper, the character he plays on “Mad Men.” The hard-drinking serial cheater has a dark past that people sometimes like to confuse with Hamm’s reality.

Season 7, which is the final season, will return to AMC Sunday, April 5, at 10 p.m. EDT. The Internet Movie Database describes the series as: “A drama about one of New York's most prestigious ad agencies at the beginning of the 1960s, focusing on one of the firm's most mysterious but extremely talented ad executives, Donald Draper.”

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