According to Emily Lane of NOLA.com, U.S. District Judge Jane Triche Milazzo deemed the 10-year deal that Sharper previously struck too lenient.
Sharper pleaded guilty to two counts of forcible rape and one count of simple rape last June. Per Lane, Milazzo said that federal sentencing guidelines suggest that a 15- to 20-year sentence is more fitting for his crimes.
According to Lane, Sharper is alleged to have either drugged or sexually assaulted nine women in four states from August 2013 through January 2014.
Sharper must now decide if he wants to withdraw his guilty plea prior to his sentencing hearing on March 3, and Milazzo made it clear that refusing to do so could lead to a harsher sentence.
The 40-year-old former safety spent 14 seasons in the NFL with the Green Bay Packers, Minnesota Vikings and New Orleans Saints.
He registered 63 career interceptions, was named to five Pro Bowls and won Super Bowl XLIV with the Saints.
Sharper's original sentence would have allowed him to serve between nine and 10 years in prison, despite it being a 20-year sentence due to legal stipulations, and it would have subjected him to lifetime probation.