4:57 PM PT -- We asked if there was any video or photo evidence to help prove Tennant's case, and her attorney essentially told us no.

4:53 PM PT -- When asked what they want to get out of the case, Tennant's attorney says they have no particular sum in mind.

4:49 PM PT -- Tennant says she did not go to law enforcement because she feared it would jeopardize her career.

Tennant's attorney says they do not intend to file a police report because they do not want to put Walton in jail.

4:43 PM PT -- Tennant says she didn't come forward at first because, "I was scared."

"I was scared for my job, my safety and what my job would be like."

She claims she's spent years trying to move past the incident and "bury it" -- but she couldn't. She says she finally mustered up the courage to tell her story.

4:40 PM PT -- Kelli Tennant got emotional while telling her story ... recounting how she felt Walton was "going to rape her" during the hotel encounter.

Tennant says she begged Walton like crazy to let her go but he ignored her pleas ... until finally giving up and letting her out of the hotel room.

"This type of behavior cannot be condoned," Tennant said.

4:33 PM PT -- Kelli says the alleged sexual assault took place in 2014, when she was 25-years-old.

Her attorney says she was uncomfortable coming forward back then but she's comfortable now.

Kelli says she met Luke Walton about 10 years ago through the volleyball community.

The woman accusing Luke Walton of sexual assault will speak with the media at 4:30 PM PT ... and TMZ Sports will be live streaming the whole thing.

Kelli Tennant and her attorney, Garo Mardirossian, will hold a press conference at his office in Los Angeles, they announced. They are both planning to speak.

Mardirossian has just issued a pre-press conference statement saying, "By way of this lawsuit, Ms. Tennant is speaking out and saying #timesup to the culture of abusing women in the NBA."

We broke the story ... Tennant -- a longtime sports reporter -- claims Walton sexually assaulted her in a Santa Monica hotel room while he was an assistant coach with the Golden State Warriors.

Walton has lawyered up and adamantly denied the allegations -- with his attorney attacking the accuser as an "opportunist."

There are TONS of unanswered questions ... what was the date of the attack? Is there any photo of video evidence? Witnesses? Etc.