LINCOLN, Neb. -- The mother of New York Yankees pitcher Joba Chamberlain faces up to 20 years in prison when she's sentenced next month on a felony drug charge.

Jackie Standley pleaded no contest Monday to an amended charge of delivery of a controlled substance, according to court records. The 44-year-old Standley was arrested in May after selling a gram of methamphetamine to an undercover officer at her Lincoln residence.

Standley originally was charged with a Class II felony, which carries a maximum sentence of 50 years, but the prosecutor reduced the charge to a Class III felony. She'll be sentenced Dec. 16.

Phone calls to a number listed for Standley went unanswered Tuesday.

The Yankees play Game 6 of the World Series against Philadelphia on Wednesday.