Add Khabib Nurmagomedov to the ever-growing list of people outraged Cain Velsaquez remains in a northern Cali cell ... with the undefeated fighter telling TMZ Sports he feels so bad for the former heavyweight champ, he's visiting him in jail next week.
"Yesterday, I was talking with coach. I tell him any chance or is it possible to go and see him in jail? In Russia, we can go and see anybody like I asked him because I don't know the law here in the U.S. I really wanna go to see him. After a couple of days, I'm gonna be in San Jose. I wanna go to see him, shake his hand, give him good energy."
33-year-old Khabib has been friends and gym mates at AKA with 39-year-old Velasquez ... who's been locked up since February 28 ... on an attempted murder charge.
But, that doesn't even begin to tell the whole story ... 'cause the person Cain allegedly tried to take out is accused of doing something very bad to a family member.
In an effort to protect the alleged victim in Velasquez's family, we are not identifying the person.
"Anybody in the world who respects himself, who loves his family -- he's gonna do same thing," Khabib passionately said.
"C'mon, nobody gonna think about law or something when you have something about your family. You have to protect your family."
Nurmagomedov, like many, can't understand why Cain's behind bars, but the man accused of the heinous act against CV's family member is free.
"This is not fair to sit in jail and other guy, he's outside. What about other guy? Put this guy in jail, too! He's more dangerous for people than Cain Velasquez."
"Never in his life, he's 40-years-old, never in his life did he have a problem in social, you know, outside with people. He's the most respectful guy I've ever seen in my life. I was training with him more than 10 years, I know his family, everybody."
Still, despite the outpouring of support, and his attorney's fighting for his freedom, the judge and prosecutor have refused to allow bail.
Velasquez, if convicted, is facing many years in prison.