'Matlock's David Del Rio Exploring Legal Options After CBS Firing

David Del Rio is exploring legal options after he was fired from 'Matlock' following an accusation of the sexual assault of a costar ... and TMZ has learned there is a lot more to his side of the story that's forthcoming.

Sources familiar with the situation tell TMZ ... David, his wife and his team are having ongoing conversations with lawyers about the situation.

TMZ broke the story ... David was escorted off the Paramount lot and fired from the hit drama reboot earlier this month ... after Leah Lewis accused him of sexually assaulting her on the Paramount lot.

A source told us Leah filed an allegation with CBS against David on Oct. 2 for an alleged sex assault she claims occurred Sept. 26. We were told on the day of the report, he was removed from the lot ... and after an investigation, he was fired. CBS Studios confirmed his character, a lead in the series, will be written off.

The LAPD tells us there's no record that an assault report was filed for the date and location of the allegation.

Shortly after we broke the news of David getting the boot after the allegation, Leah shared a pic of herself embracing her mother, writing ... "Mom is here, we're moving forward in love and strength. I'm in good hands. Thank you to everybody for any kind of support and care. Truly, we're moving forward in strength. Key word, strength. Please, let that be the take away."

David's wife, Katherine, also quickly responded to the situation ... calling Lewis "the most disturbing human being I have ever met."

The series has a pre-planned hiatus in October and November upon completion of the first half of the season. "Matlock" Season 2 premiered Sunday on CBS.