3:50 PM PT -- There was a bombshell moment in court when prosecutors added 2 new rape charges stemming from an alleged incident in 2003 where Kellen -- 19 years old at the time -- was accused of forcibly raping a 17 year old unconscious girl.

"When there is a rape that occurs and the victim is under the age of 18 years old, there is no statutory time (limit) to when that can be charged. That's exactly what we have here."

Kellen Winslow's rape case is now set to go to trial -- he faces life in prison -- and today the judge finally set bail at $2 million.

Thursday's hearing was a win of sorts for the former NFL tight end who's been locked up ever since he was arrested on June 14 on suspicion of raping 2 women in the San Diego area.

Now, Winslow can post bail and leave jail. A trial date has not yet been set.

As TMZ Sports previously reported ... Winslow was initially hit with nine criminal charges after prosecutors say he picked up 2 hitchhiking transients, drove them to an isolated location and raped them.

Prosecutors also say Winslow entered a mobile home park on two occasions with the intent of raping elderly women.

He was previously charged with 2 counts of residential burglary -- but those have now been thrown out.