Former Full House actor John Stamos has been accused of having a romantic relationship with a 17-year-old girl.

The claim came out during a court case against Allison Coss, 24, who, along with her boyfriend, is accused of trying to blackmail the star out of hundreds of thousands of dollars after threatening to go public with alleged photos of him cavorting with strippers and cocaine.

During court proceedings in Michigan Monday, the woman’s attorney claimed that Stamos had a fling with Coss when she was a 17-year-old high school student in Florida back in 2004. John, now 46, is accused of buying an alcoholic drink for the underage girl then stripping off with her in a hot tub, although he was fully in the know about her less than legal status. When she refused to have sex with him, he allegedly punched and broke a bedpost in his hotel room.

According to Coss, for the next few years, the pair reportedly maintained a “flirty kind of relationship” by email.

Perhaps, not surprisingly, reps for the TV star vehemently deny claims that Stamos romanced a then-teenage Allison. The actor’s attorney has denied the claims and issued the following public statement: “The allegations made today in the courtroom by the defendants during opening statements will not be proven because they are simply untrue.”