Griffin was driving in Escondido, CA on Tuesday, when his vehicle veered into oncoming traffic and crashed into another car, police sources told The AP.
46-year-old Griffin was taken to a nearby medical centre and later released after doctors determined he was in stable condition.
It's not yet known if the driver of the other vehicle was hurt.
The car accident occurred hours after Griffin's half-brother Redmond was arrested on a drug charge in Los Angeles.
Police officers reportedly found heroin in Redmond's car after pulling him over for a traffic violation.
Griffin and Redmond's sister Tatum asked her Twitter followers to pray for both men, writing: "My Oneal brothers are not doing that great right now. Will take a prayer if you have it in you (sic)."
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