Oksana Grigorieva’s legal team has suffered another blow -- her top family law attorney Allen Shiftman has quit the case, RadarOnline.com has exclusively learned.

He delivered the sudden news to the Russian musician a short time ago.

EXCLUSIVE PHOTOS: See The First Photos of Mel and Oksana In a Passionate Embrace On The Beach

Shiftman, a top Los Angeles family law specialist, replaced Mitchell Jacobs, who resigned last month, citing frustration with some of Oksana’s other legal advisors.

Jacobs had replaced high powered Hollywood attorney Sorrell Trope, who Oksana sacked — after sacking two other firms.

A Los Angeles judge has ordered Mel Gibson to pay his baby-mama tens of thousands of dollars in back child support and give up his legal fight to charge her rent to live in his home, RadarOnline.com has exclusively learned.

Mel, 54, and Oksana Grigorieva, 40, are still locked in a closed courtroom for the latest round in their custody battle over daughter Lucia, one.

PHOTOS:  Mel & Oksana In Happier Times

But RadarOnline.com has learned that inside Los Angeles Superior Court, Judge Scott Gordon told the Oscar-winning actor he could not charge Oksana and Lucia rent to live in his Sherman Oaks, California, home.

Mel Gibson's high-powered criminal attorney Blair Berk has just been served, RadarOnline.com has learned.

The top lawyer emerged from a Los Angeles courtroom about 11.30am PT and was immediately served a subpoena.

PHOTOS: Mel And Oksana In Happier Times

It's unknown what the subpoena related to and the process server, one of Oksana's lawyers Allen Shiftman, would not reveal why.

"You are serving me in the hallway," a furious Berk told Shiftman.