A Janesville teen was sentenced to prison Wednesday after failing to complete his probation. Austin Groebner had his sentence withheld on a charge of theft while armed, which had been reduced from armed robbery and if he could complete three years probation successfully the felony charge and threat of prison would go away. Four months after he was sentenced Groebner and an accomplice robbed a man who thought he was going to sell THC smoking cartridges to the teens, instead they beat him up and robbed him of the cartridges. Groebner was sentenced to three years in prison with three years extended supervision stemming from the original charge of pointing an airsoft gun at a man in Bond Park and took his cellphone and wallet. The judge warned him that if he fails on probation he will face more jail time. Groebner will have access to prison programs to help deal with his drug problem and these programs will give him a chance at getting out of prison early. He’s also earned a sentence credit of 345 days.