New England Patriots safety Jabrill Peppers appeared in a Massachusetts courtroom on Thursday and pled guilty to one charge of possessing cocaine.

The 29-year-old -- wearing a blue suit and white shirt -- admitted to a judge that the powdery substance that was found in his wallet following his arrest for domestic violence in October was the illegal drug.

The football player was ordered to remain drug-free and stay out of trouble for the next four months after making his plea.

Peppers is still facing three other charges related to the arrest -- including counts of strangulation and assault and battery -- as authorities say he roughed up his girlfriend during an early morning argument on Oct. 5.

Cops say the woman told them Peppers shoved her head into a wall and choked her during the incident. Peppers, though, is adamant he did nothing wrong ... and his attorney claims they have videos that help prove his innocence.

The case's trial -- which was postponed from Wednesday following an unexpected water main break at the courthouse -- is slated to begin later Thursday ... with jury selection beginning in a matter of minutes.

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