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AUSTIN(AP/CBSDFW) – Police say they are investigating an incident involving Johnny Manziel that led to a lawsuit from a man who claims the Heisman Trophy-winning quarterback punched him and broke his nose in a bar in Austin.

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The lawsuit was filed Monday, three days before the former Texas A&M star was due in court in Dallas for the potential dismissal of a domestic violence case against him. The alleged incident happened in September at a bar in the popular Sixth Street entertainment district in downtown Austin.

The plaintiff, Eric Newton, said Manziel was attending a private party when Newton turned down Manziel’s request to prepare some drinks. Newton said he was later discussing his opinion of Manziel with another customer and that somebody in Manziel’s group told the former Cleveland Browns quarterback about the conversation.

Newton claims that Manziel “came downstairs, ran behind the bar, cursed at Mr. Newton, and punched him in the face, breaking Mr. Newton’s nose.”

Austin police wouldn’t release details of an incident report, saying it had been marked “private” by an investigator.

A spokeswoman for Manziel said his representatives were aware of the lawsuit but didn’t comment further.

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Manziel appeared in a Dallas courtroom on the morning of November 17th for a hearing on his domestic violence charge.

According to reports, Manziel reached a tentative deal with prosecutors for the conditional dismissal of the case involving his former girlfriend.

Defense attorney Jim Darnell said there was still work to be done to finalize the deal, but said after a Thursday morning hearing that he was encouraged. A judge set another hearing for Dec. 1, when the case could be settled.

The troubled former Cleveland quarterback left the courtroom without responding to questions.

The 23-year-old Manziel is accused of hitting and threatening former girlfriend Colleen Crowley during a night out in January.

The former star at Texas A&M faces a misdemeanor assault charge that carries a penalty of up to a year in jail and a $4,000 fine for that incident.

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