Usher's ex-wife seeking custody of their 5-year-old after freak swimming pool accident sends him to hospital!

Usher's 5-year-old son nearly drowned in a backyard pool in Atlanta on Monday — setting off what could be an ugly custody battle after the boy’s mom apparently blamed the Grammy-Award winner for the accident.

The R&B singer was not at the home where the terrifying incident occurred, a report said.

But Usher’s ex-wife, the boy’s mother, seems to be holding the entertainer responsible anyway.

Tameka Foster — who lost another child by a different father in a Jet Ski accident — filed legal documents Tuesday to try to gain custody of little Usher Raymond 5th, citing a dangerous environment.

The drama began Monday when the boy ended up at the bottom of a pool behind a home in downtown Atlanta and became stuck in a drain, police said. He was trying to retrieve a toy, TMZ reported.

It was unclear if the home belonged to his famous father, but the child’s aunt, Rena Oden, was there. She, a housekeeper and a third woman tried to save the boy but failed, CNN reported.

That’s when two men who were working at the home as contractors came dashing to the rescue.

They dived in, freed the drowning child and pulled him out. One of the contractors gave the boy CPR — and he was “conscious, alert and breathing” by the time paramedics arrived, cops said. CNN identified the hero sound technician as Eugene Stachurski.

Before the ambulance showed up, Oden made a frantic phone call to 911. TMZ posted an audio recording. “My nephew was in the pool,” Oden tells the 911 operator. “I tried to get him ... They got him right now out there with CPR.”

“Is he coming around?” she is heard asking. “He’s breathing!” she told the operator.

Usher, 34, and his ex-wife were by their son’s bedside Tuesday, TMZ said.

Doctors were expecting a full recovery, the site reported.

Usher Raymond 5th is the older of two brothers. His parents divorced in 2009 after two years of marriage and became embroiled in a legal battle over custody. Usher was awarded primary custody last year, TMZ said.

Foster, 42, is still recovering from last year’s death of another son — 11-year-old Kile Glover, her child with another man.

“My son is okay, but I have no further comment at this time,” she told CNN on Tuesday.

Tameka Foster reportedly filed for custody a day after son Usher Raymond V was rescued from 

pool drain, citing a dangerous environment.