ATLANTIC CITY — Phillies outfielder Odubel Herrera, scheduled to appear Monday afternoon in Atlantic City Municipal Court on charges that he assaulted his girlfriend inside a casino, has waived his initial appearance, according to court officials.

On Monday afternoon, Major League Baseball announced that it had extended Herrera’s administrative leave, which was set to expire Monday, through July 1.

Herrera, identified in court documents as David O. Herrera, was charged May 27 with simple assault and knowingly causing bodily injury after his 20-year-old girlfriend, who had handprint markings on her neck and scratches on her arm, told security at the Golden Nugget casino that he had attacked her .

The casino security officers called Atlantic City police, who went to Herrera’s room and took him into custody, according to police reports. Later, police notified the Phillies and put out a news release.

According to a tweet Monday morning from the Atlantic City Police Department, which cited Municipal Court, Herrera’s attorney waived the first appearance, allowing the case to proceed. The police said another hearing would be scheduled by the court.

Nioby Mejia, a Municipal Court administrator in Atlantic County, confirmed that Herrera’s attorney had waived first appearance and that a new date had not yet been set. The attorney, Thomas Calcagni, did not immediately return a message.

Staff writer Matt Breen contributed to this article.