A federal judge has set a Thursday hearing on the guilty pleas that former Saints safety and admitted serial rapist Darren Sharper entered provisionally last year to three drug counts as part of a wider agreement to resolve drugging and rape allegations involving nine women in four states.

U.S. District Judge Jane Triche Milazzo has billed it only as a “plea hearing,” giving no clear indication about what is slated to take place.

The new hearing, however, comes on the heels of a joint motion filed this month by Sharper’s attorneys and U.S. Attorney Kenneth Polite’s office, indicating that the retired defensive back’s elaborate deal with prosecutors from multiple jurisdictions has hit the skids.

The motion asked for a delay in a trial date for Sharper and the two men with whom he is accused of drugging women with the intention of raping them: former St. Bernard Parish Sheriff’s Office Deputy Brandon Licciardi and former steakhouse waiter Erik Nunez.

It appears Milazzo has declined to rubber-stamp Sharper’s plea deal, which had called for him to serve nine years in federal prison, though the judge has not formally ruled on it.

“Recent developments have led to a resumption of plea negotiations; prior to that, neither party expected Mr. Sharper to go to trial,” the joint motion stated. “The change in case posture ... has now dictated that the defendant and the prosecution must now prepare for a more complex trial.”

Milazzo granted that motion, pushing a March trial date back by two months, to May 16, almost a year after Sharper pleaded guilty to federal drug conspiracy and distribution counts.

The judge accepted Sharper’s guilty pleas in May but held them in abeyance pending a federal probation report that, according to a law enforcement source, sets the recommended sentencing range for Sharper well above the nine years he would serve in federal prison under his deal.

Under his agreement, Sharper would then embark on a lifetime of parole and probation restrictions.

His federal plea is one piece of a “global” agreement hashed out among Sharper’s attorneys, federal authorities and state prosecutors in California, Arizona, Nevada and Louisiana.

The deal has drawn criticism from some quarters for being too lenient, and it appears to have met a roadblock with Milazzo, who by law can endorse or reject its terms but not alter them.

If Sharper’s attorneys are unable to salvage the deal, federal prosecutors likely would need to secure a new grand jury indictment against him, because the current indictment in the case names only Licciardi and Nunez, both of whom have pleaded not guilty.

Licciardi and Nunez also are named, along with Sharper, in a nine-count Orleans Parish state indictment that accuses all three men of committing aggravated rape, which carries a life prison term.

Sharper pleaded guilty last June to two state counts of forcible rape and a charge of simple rape in Orleans Parish. The former All-Pro admitted he raped three women in two separate incidents in 2013 while retired from football and working as an NFL Network analyst.

Sharper was tentatively scheduled for sentencing on Wednesday before Criminal District Court Judge Karen Herman, who pushed back the sentencing to June 14. Herman has said she would wait to sentence Sharper until after Milazzo has done the same.

Complicating matters, for Sharper at least, are terms of his plea deal that required him to debrief with investigators and cooperate in other prosecutions. The deal allows prosecutors to use those interviews against him should he withdraw his guilty pleas.

Sharper’s attorney in New Orleans, Billy Gibbens, did not immediately return a call Tuesday.

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